- Catalytic Asymmetric Allylic Substitution with Copper(I) Homoenolates Generated from Cyclopropanols
-
By using copper(I) homoenolates as nucleophiles, which are generated through the ring-opening of 1-substituted cyclopropane-1-ols, a catalytic asymmetric allylic substitution with allyl phosphates is achieved in high to excellent yields with high enantioselectivity. Both 1-substituted cyclopropane-1-ols and allylic phosphates enjoy broad substrate scopes. Remarkably, various functional groups, such as ether, ester, tosylate, imide, alcohol, nitro, and carbamate are well tolerated. Moreover, the present method is nicely extended to the asymmetric construction of quaternary carbon centers. Some control experiments argue against a radical-based reaction mechanism and a catalytic cycle based on a two-electron process is proposed. Finally, the synthetic utilities of the product are showcased by means of the transformations of the terminal olefin group and the ketone group.
- Shi, Chang-Yun,Yin, Liang,Zhang, Qi,Zhou, Si-Wei
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supporting information
p. 26351 - 26356
(2021/11/09)
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- New hybrid compounds combining fragments of usnic acid and monoterpenoids for effective tyrosyl-dna phosphodiesterase 1 inhibition
-
Usnic acid (UA) is a secondary metabolite of lichens that exhibits a wide range of biological activities. Previously, we found that UA derivatives are effective inhibitors of tyrosyl-DNA phosphodiesterase 1 (TDP1). It can remove covalent complex DNA-topoisomerase 1 (TOP1) stabi-lized by the TOP1 inhibitor topotecan, neutralizing the effect of the drugs. TDP1 removes damage at the 3′ end of DNA caused by other anticancer agents. Thus, TDP1 is a promising therapeutic target for the development of drug combinations with topotecan, as well as other drugs for cancer treatment. Ten new UA enamino derivatives with variation in the terpene fragment and substituent of the UA backbone were synthesized and tested as TDP1 inhibitors. Four compounds, 11a-d, had IC50 values in the 0.23–0.40 μM range. Molecular modelling showed that 11a-d, with relatively short aliphatic chains, fit to the important binding domains. The intrinsic cytotoxicity of 11a-d was tested on two human cell lines. The compounds had low cytotoxicity with CC50 ≥ 60 μM for both cell lines. 11a and 11c had high inhibition efficacy and low cytotoxicity, and they enhanced topotecan’s cyto-toxicity in cancerous HeLa cells but reduced it in the non-cancerous HEK293A cells. This “protec-tive” effect from topotecan on non-cancerous cells requires further investigation.
- Dyrkheeva, Nadezhda S.,Filimonov, Aleksandr S.,Luzina, Olga A.,Zakharenko, Alexandra L.,Ilina, Ekaterina S.,Malakhova, Anastasia A.,Medvedev, Sergey P.,Reynisson, Jóhannes,Volcho, Konstantin P.,Zakian, Suren M.,Salakhutdinov, Nariman F.,Lavrik, Olga I.
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- New sustainable synthetic routes to cyclic oxyterpenes using the ecocatalyst toolbox
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Cyclic oxyterpenes are natural products that are mostly used as fragrances, flavours and drugs by the cosmetic, food and pharmaceutical industries. However, only a few cyclic oxyterpenes are accessible via chemical syntheses, which are far from being ecofriendly. We report here the synthesis of six cyclic oxyterpenes derived from ?-pinene while respecting the principles of green and sustainable chemistry. Only natural or biosourced catalysts were used in mild conditions that were optimised for each synthesis. A new generation of ecocatalysts, derived from Mn-rich water lettuce, was prepared via green processes, characterised by MP-AES, XRPD and TEM analyses, and tested in catalysis. The epoxidation of ?-pinene led to the platform molecule, ?-pinene oxide, with a good yield, illustrating the efficacy of the new generation of ecocatalysts. The opening ?-pinene oxide was investigated in green conditions and led to new and regioselective syntheses of myrtenol, 7-hydroxy-α-terpineol and perillyl alcohol. Successive oxidations of perillyl alcohol could be performed using no hazardous oxidant and were controlled using the new generation of ecocatalysts generating perillaldehyde and cuminaldehyde.
- Bihanic, Camille,Grison, Claude,Lasbleiz, Arthur,Le Blainvaux, Pierre,Petit, Eddy,Regnier, Morgan
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-
- Preparation of α-terpineol and perillyl alcohol using zeolites beta
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The preparation of α-terpineol by direct hydration of limonene catalyzed by zeolites beta was studied. The same catalyst was used to prepare perillyl alcohol by isomerization of β-pinene oxide in the presence of water. The aim was to optimize the reaction conditions to achieve high conversions of starting material and high selectivity to the desired products. In the case of limonene, it was found that the highest selectivity to α-terpineol was 88% with conversion of 36% under the conditions: 50?wt% of catalyst beta 25, 10% aqueous acetic acid (10?mL) (volume ratio limonene:H2O = 1:4.5), temperature 50?°C, after 24?h. In the case of β-pinene oxide, it was found that the highest selectivity to perillyl alcohol, which was 36% at total conversion, was obtained in the reaction under the following conditions: dimethyl?sulfoxide as solvent (volume ratio β-pinene oxide:DMSO = 1:5), catalyst beta 25 without calcination (15?wt%), demineralized water (molar ratio β-pinene oxide:H2O = 1:8), temperature 70?°C, 3?h. The present study shows that the studied reactions are suitable for the selective preparation of chosen compounds.
- ?erveny, Libor,Vysko?ilová, Eli?ka,Zítová, Kate?ina
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p. 4297 - 4310
(2021/07/26)
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- Selective Catalytic Isomerization of β-Pinene Oxide to Perillyl Alcohol Enhanced by Protic Tetraimidazolium Nitrate
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A series of tetraimidazolium salts with different anions was prepared and applied in the isomerization of β-pinene oxide. After examining the activity of different catalysts, a remarkable enhancement of the selectivity of perillyl alcohol (47 %) was obtained over [PEimi][HNO3]4 under mild reaction conditions and using DMSO as the solvent. Furthermore, noncovalent interactions between solvent molecules and the catalyst were found by FT-IR spectroscopy and confirmed by computational chemistry. The homogeneous catalyst showed excellent stability and was reused up to six times without significant loss.
- Li, Hui,Liu, Jian,Zhao, Juan,He, Huiting,Jiang, Dabo,Kirk, Steven Robert,Xu, Qiong,Liu, Xianxiang,Yin, Dulin
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p. 477 - 485
(2021/05/04)
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- Ambient-pressure highly active hydrogenation of ketones and aldehydes catalyzed by a metal-ligand bifunctional iridium catalyst under base-free conditions in water
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A green, efficient, and high active catalytic system for the hydrogenation of ketones and aldehydes to produce corresponding alcohols under atmospheric-pressure H2 gas and ambient temperature conditions was developed by a water-soluble metal–ligand bifunctional catalyst [Cp*Ir(2,2′-bpyO)(OH)][Na] in water without addition of a base. The catalyst exhibited high activity for the hydrogenation of ketones and aldehydes. Furthermore, it was worth noting that many readily reducible or labile functional groups in the same molecule, such as cyan, nitro, and ester groups, remained unchanged. Interestingly, the unsaturated aldehydes can be also selectively hydrogenated to give corresponding unsaturated alcohols with remaining C=C bond in good yields. In addition, this reaction could be extended to gram levels and has a large potential of wide application in future industrial.
- Wang, Rongzhou,Yue, Yuancheng,Qi, Jipeng,Liu, Shiyuan,Song, Ao,Zhuo, Shuping,Xing, Ling-Bao
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-
- Method for synthesizing unsaturated primary alcohol in water phase
-
The invention discloses a method for synthesizing unsaturated primary alcohol in a water phase. The method comprises the following steps: taking unsaturated aldehyde as a raw material, selecting water as a solvent, and carrying out catalytic hydrogenation reaction on the unsaturated aldehyde in the presence of a water-soluble catalyst to obtain the unsaturated primary alcohol, wherein the catalyst is a metal iridium complex [Cp * Ir (2, 2'-bpyO)(OH)][Na]. Water is used as the solvent, so that the use of an organic solvent is avoided, and the method is more environment-friendly; the reaction is carried out at relatively low temperature and normal pressure, and the reaction conditions are mild; alkali is not needed in the reaction, so that generation of byproducts is avoided; and the conversion rate of the raw materials is high, and the yield of the obtained product is high. The method not only has academic research value, but also has a certain industrialization prospect.and.
- -
-
Paragraph 0036-0037
(2021/07/14)
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- One-Pot Absolute Stereochemical Identification of Alcohols via Guanidinium Sulfate Crystallization
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A novel technique for the absolute stereochemical determination of alcohols has been developed that uses crystallization of guanidinium salts of organosulfates. The simple one-pot, two-step process leverages facile formation of guandinium organosulfate single crystals for the straightforward determination of the absolute stereochemistry of enantiopure alcohols by means of X-ray crystallography. The strong hydrogen bonding network drives the stability of the crystal lattice and allows for a diverse range of organic alcohol substrates to be analyzed.
- Brummel, Beau R.,Lee, Kinsey G.,McMillen, Colin D.,Kolis, Joseph W.,Whitehead, Daniel C.
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p. 9622 - 9627
(2019/12/02)
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- Oxy-functionalization of olefins with neat and heterogenized binuclear V(IV)O and Fe(II)complexes: Effect of steric hindrance on product selectivity and output in homogeneous and heterogeneous phase
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Neat {[VO(sal2bz)]2; [Fe(sal2bz)(H2O)2]2·2H2O} and zeolite-Y immobilized {[VO(sal2bz)]2-Y; [Fe(sal2bz)(H2O)2]2-Y} binuclear complexes have been prepared and characterized by spectroscopic techniques (IR, UV–vis), elemental analyses (CHN, ICP-OES), thermal study (TGA), scanning electron micrograph (SEM), adsorption study (BET)and X-ray diffraction (XRD)patterns. Neat (homogeneous)and immobilized (heterogeneous)complexes were employed as catalysts in the oxidation of olefins, namely, cyclohexene, limonene and α-pinene in the presence of 30% hydrogen peroxide. 100% conversion of cyclohexene and α-pinene was obtained while limonene was oxidized up to 90%. Homogeneous catalysts showed highly selective result as neat [VO(sal2bz)]2 complex has provided 87% cyclohexane-1,2-diol and neat [Fe(sal2bz)(H2O)2]2·2H2O complex has provided 79% verbenone in oxidation of cyclohexene and α-pinene, respectively. We have observed that due to steric hindrance, formation of olefinic oxidation products increases on moving from α-pinene to limonene and limonene to cyclohexene. Additionally. recovered heterogeneous catalysts showed intact results up to two consecutive runs. Probable catalytic mechanism has been proposed for oxidation of cyclohexene.
- Parmar, Digvijaysinh K.,Butani, Pinal M.,Thumar, Niraj J.,Jasani, Pinal M.,Padaliya, Ravi V.,Sandhiya, Paba R.,Nakum, Haresh D.,Khan, Md. Nasim,Makwana, Dipak
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- Perilla alcohol derivative and its preparation and use
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The invention belongs to the technical field of medicine, and relates to a series of perilla alcohol derivatives disclosed as Formula I, and preparation and application thereof. The invention also relates to pharmaceutically acceptable salts and solvates of the perilla alcohol derivatives, and a pharmaceutical composition containing the perilla alcohol derivatives or pharmaceutically acceptable salts thereof as active components, which can be used for treating cancers. The perilla alcohol derivatives and pharmaceutical salts thereof have favorable anticancer activity. The preparation method is simple and feasible, and is easy to operate.
- -
-
Paragraph 0025; 0026
(2018/04/02)
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- Perilla amine compound and its preparation and use (by machine translation)
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The invention belongs to the field of medical technology, involves a series of formula I structure perilla amine compound and its preparation and use. The states the perilla amine compound includes pharmaceutically acceptable salts and solvates, and states the perilla amines containing the compound or its pharmaceutically acceptable salt as an active ingredient of the composition, can be used for treating cancer. The invention the perilla amine compounds and their pharmaceutically acceptable salts has better anti-cancer activity, its preparation method is simple and feasible, and easy to operate. (by machine translation)
- -
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Paragraph 0028; 0029
(2018/04/02)
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- Selective Base-free Transfer Hydrogenation of α,β-Unsaturated Carbonyl Compounds using iPrOH or EtOH as Hydrogen Source
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Commercially available Ru-MACHOTM-BH is an active catalyst for the hydrogenation of several functional groups and for the dehydrogenation of alcohols. Herein, we report on the new application of this catalyst to the base-free transfer hydrogenation of carbonyl compounds. Ru-MACHOTM-BH proved to be highly active and selective in this transformation, even with α,β-unsaturated carbonyl compounds as substrates. The corresponding aliphatic, aromatic and allylic alcohols were obtained in excellent yields with catalyst loadings as low as 0.1–0.5 mol % at mild temperatures after very short reaction times. This protocol tolerates iPrOH and EtOH as hydrogen sources. Additionally, scale up to multi-gram amounts was performed without any loss of activity or selectivity. An outer-sphere mechanism has been proposed and the computed kinetics and thermodynamics of crotonaldehyde and 1-phenyl-but-2-en-one are in perfect agreement with the experiment.
- Farrar-Tobar, Ronald A.,Wei, Zhihong,Jiao, Haijun,Hinze, Sandra,de Vries, Johannes G.
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supporting information
p. 2725 - 2734
(2018/02/28)
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- Hydrogenation and Reductive Amination of Aldehydes using Triphos Ruthenium Catalysts
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An air-stable and readily accessible ruthenium dihydride complex catalyses aldehyde hydrogenation under neutral conditions. A high activity has been shown in a number of examples, and solvent-free conditions are also applicable, which favours industrial-scale applications. The catalyst has also been demonstrated to be active at low catalyst loadings for the reductive amination of aldehydes under mildly acidic conditions. A number of examples of chemoselectivity challenges are also presented in which the catalyst does not reduce carbon?halogen groups, alkene or ketone functionality. The advantage of using the pre-formed complex, Triphos-Ru(CO)H2 (1), over in situ formed catalysts from Triphos and Ru(acac)3 (acac=acetylacetonate) is also shown in terms of both chemoselectivity and activity, in particular this can be seen if low reaction temperatures are used.
- Christie, Francesca,Zanotti-Gerosa, Antonio,Grainger, Damian
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p. 1012 - 1018
(2018/01/27)
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- Intramolecular [2 + 2] Cycloadditions of Alkyl(phenylthio)ketenes: Total Synthesis of (+)-Sphaerodiol
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Asymmetric total synthesis of (+)-sphaerodiol (2) has been achieved. A key step is an intramolecular [2 + 2] cycloaddition of alkyl(phenylthio)ketene for rapid assembly of the decalin ring.
- Wu, Xiang,Wang, Hai-Jun,Huang, Yong-Shuang,Li, Wei-Dong Z.
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supporting information
p. 1871 - 1874
(2018/04/16)
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- Rhodium-Catalyzed Synthesis of α,β-Unsaturated Ketones through Sequential C-C Coupling and Redox Isomerization
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A novel Rh(I)-catalyzed sequential C-C coupling and redox isomerization between allylic alcohols and 1,3-dienes has been accomplished. This versatile protocol provides expeditious access to a broad range of polysubstituted α,β-unsaturated ketones with excellent atom economy and regioselectivity.
- Li, Hong-Shuang,Guo, Guili,Zhang, Rui-Ze,Li, Fei
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supporting information
p. 5040 - 5043
(2018/08/24)
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- SELECTIVE REDUCTION OF ALDEHYDES AND KETONES
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The present invention relates to a selective reduction of specific aldehydes and ketones to their corresponding alcohols.
- -
-
Page/Page column 47; 48; 49
(2017/12/01)
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- Kinetics of the Aqueous Phase Reactions of Atmospherically Relevant Monoterpene Epoxides
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Laboratory and field measurements have demonstrated that an isoprene-derived epoxide intermediate (IEPOX) is the origin of a wide range of chemical species found in ambient secondary organic aerosol (SOA). In order to explore the potential relevance of a similar mechanism for the formation of monoterpene-derived SOA, nuclear magnetic resonance techniques were used to study kinetics and reaction products of the aqueous-phase reactions of several monoterpene epoxides: β-pinene oxide, limonene oxide, and limonene dioxide. The present results, combined with a previous study of α-pinene oxide, indicate that all of these epoxides will react more quickly than IEPOX with aqueous atmospheric particles, even under low-acidity conditions. As for α-pinene oxide, the observed products can be mainly rationalized with a hydrolysis mechanism, and no long-lived organosulfate or nitrate species nor species that retain the β-pinene bicyclic carbon backbone are observed. As bicyclic ring-retaining organosulfate and nitrate species have been previously observed in monoterpene-derived SOA, it appears that monoterpene-derived epoxides may not be as versatile as IEPOX in producing a range of SOA species, and other mechanisms are needed to rationalize organosulfate and nitrate formation.
- Cortés, DIego A.,Elrod, Matthew J.
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p. 9297 - 9305
(2017/12/18)
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- Selective Hydrogenation of α,β-Unsaturated Aldehydes and Ketones by Air-Stable Ruthenium NNS Complexes
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The selective hydrogenation of the carbonyl functionality of α,β-unsaturated aldehydes and ketones is catalysed by ruthenium dichloride complexes bearing a tridentate NNS ligand as well as triphenylphosphine. The tridentate ligand backbone is flexible, as evidenced by the equilibrium observed in solution between the cis- and trans-isomers of the dichloride precatalysts, as well as crystal structures of several of these complexes. The complexes are activated by base in the presence of hydrogen and readily hydrogenate carbonyl functionalities under mild conditions. Despite the activation by base, side reactions are negligible, even for aldehyde substrates, because of the low amount of base. Thus, the corresponding allylic alcohols can be isolated in very good yields on a 10–25 mmol scale. Turnover numbers up to 200 000 were achieved.
- Puylaert, Pim,van Heck, Richard,Fan, Yuting,Spannenberg, Anke,Baumann, Wolfgang,Beller, Matthias,Medlock, Jonathan,Bonrath, Werner,Lefort, Laurent,Hinze, Sandra,de Vries, Johannes G.
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p. 8473 - 8481
(2017/06/28)
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- Selective Catalytic Hydrogenations of Nitriles, Ketones, and Aldehydes by Well-Defined Manganese Pincer Complexes
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Hydrogenations constitute fundamental processes in organic chemistry and allow for atom-efficient and clean functional group transformations. In fact, the selective reduction of nitriles, ketones, and aldehydes with molecular hydrogen permits access to a green synthesis of valuable amines and alcohols. Despite more than a century of developments in homogeneous and heterogeneous catalysis, efforts toward the creation of new useful and broadly applicable catalyst systems are ongoing. Recently, Earth-abundant metals have attracted significant interest in this area. In the present study, we describe for the first time specific molecular-defined manganese complexes that allow for the hydrogenation of various polar functional groups. Under optimal conditions, we achieve good functional group tolerance, and industrially important substrates, e.g., for the flavor and fragrance industry, are selectively reduced.
- Elangovan, Saravanakumar,Topf, Christoph,Fischer, Steffen,Jiao, Haijun,Spannenberg, Anke,Baumann, Wolfgang,Ludwig, Ralf,Junge, Kathrin,Beller, Matthias
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supporting information
p. 8809 - 8814
(2016/07/29)
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- Biomass to value added chemicals: Isomerisation of β-pinene oxide over supported ionic liquid catalysts (SILCAs) containing Lewis acids
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The isomerisation of β-pinene oxide was studied over supported ionic liquid catalysts (SILCAs) consisting of Lewis acids in immobilized ionic liquid. SILCAs were demonstrated as efficient catalysts for the transformation of β-pinene oxide to myrtanal with the product distribution and activity being dependent on the nature of the ionic liquid and Lewis acid strength of catalytic species. With the catalyst ZnCl2/[N(3-OH-Pr)Py][NTf2]/ACC, the highest myrtanal molar yield obtained was 68%.
- Salminen, Eero,Rujana, Luis,M?ki-Arvela, P?ivi,Virtanen, Pasi,Salmi, Tapio,Mikkola, Jyri-Pekka
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p. 318 - 321
(2015/09/28)
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- Simple and expeditious pinacol coupling of non usual α,β-unsaturated carbonyl compounds in water
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Using zinc (0) in a 5% v AcOH aqueous solution allowed the efficient pinacol coupling of aliphatic or aromatic unusual, α,β-unsaturated carbonyl compounds such as citral A in good to excellent yields (56-99%). It can also be successfully applied to acetophenone.
- Billamboz, Muriel,Sotto, Nicolas,Chevrin-Villette, Carole,Len, Christophe
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p. 46026 - 46030
(2015/06/08)
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- METHOD FOR PRODUCING UNSATURATED ALCOHOL
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PROBLEM TO BE SOLVED: To provide a method for producing an unsaturated alcohol that uses an unsaturated carbonyl compound as a raw material and can produce an unsaturated alcohol in which only the carbonyl bond of the unsaturated carbonyl compound is selectively reduced with excellent reaction rate, high selectivity and high yield. SOLUTION: The process for producing an unsaturated alcohol includes a step of allowing the reductive reaction of a 3C or more unsaturated carbonyl compound having one or more carbon-carbon unsaturated bonds in the molecule with hydrogen to proceed in the presence of a catalyst comprising at least one kind of metal selected from the group consisting of cobalt, nickel, copper, zinc, ruthenium, rhodium, palladium, silver, osmium, iridium and platinum and at least one kind of metal selected from the group consisting of vanadium, chromium, manganese, iron, molybdenum, tungsten and rhenium to produce a corresponding unsaturated alcohol. COPYRIGHT: (C)2015,JPOandINPIT
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Paragraph 0074-0076
(2017/01/02)
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- SnO2-isolated Pt3Sn alloy on reduced graphene oxide: An efficient catalyst for selective hydrogenation of CO in unsaturated aldehydes
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In this communication, a pyramid shaped alloy-metal oxide-graphene hybrid was synthesized by a facile procedure, in which SnO2 nanoparticles (NPs) (4.8-5.8 nm) were first coated onto the surface of reduced graphene oxide (rGO), and then very fine Pt3Sn NPs (0.6-1.2 nm) were fabricated on the SnO2 NPs on rGO sheets under microwave irradiation in a few minutes. Characterizations disclosed that the SnO2 NPs on rGO were more favorable for the dispersion of Pt, and Pt3Sn formed mainly on the surface of SnO2 NPs. This pyramid shaped Pt3Sn/SnO2/rGO hybrid was highly active, selective and stable for the hydrogenation of the CO bond in unsaturated aldehydes to unsaturated alcohols under mild conditions.
- Shi, Juanjuan,Zhang, Mengyuan,Du, Weichen,Ning, Wensheng,Hou, Zhaoyin
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p. 3108 - 3112
(2015/06/08)
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- Synthesis and antiproliferative effects of amino-modified perillyl alcohol derivatives
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Two series of amino-modified derivatives of (S)-perillyl alcohol were designed and synthesized using (S)-perillaldehyde as the starting material. These derivatives showed increased antiproliferative activity in human lung cancer A549 cells, human melanoma A375-S2 cells and human fibrosarcoma HT-1080 cells comparing with that of (S)-perillyl alcohol. Among these derivatives, compounds VI5 and VI7 were the most potent agents, with the IC50s below 100 μM. It was demonstrated that the antiproliferative effect of VI5 was mediated through the induction of apoptosis in A549 cells.
- Hui, Zi,Zhang, Meihui,Cong, Lin,Xia, Mingyu,Dong, Jinhua
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p. 6671 - 6682
(2014/06/10)
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- General and highly efficient iron-catalyzed hydrogenation of aldehydes, ketones, and α,β-unsaturated aldehydes
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EnvIRONmentally friendly: The title hydrogenation of aldehydes, ketones, and α,β-unsaturated aldehydes is reported. In the presence of the catalyst 1, primary, secondary, and allylic alcohols were obtained in good to excellent yields under mild reaction conditions. The catalyst is easily and inexpensively prepared, and is also stable to air, water, and column chromatography. Copyright
- Fleischer, Steffen,Zhou, Shaolin,Junge, Kathrin,Beller, Matthias
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p. 5120 - 5124
(2013/06/27)
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- A molecularly defined iron-catalyst for the selective hydrogenation of α,β-unsaturated aldehydes
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A selective iron-based catalyst system for the hydrogenation of α,β-unsaturated aldehydes to allylic alcohols is presented. Applying the defined iron-tetraphos complex [FeF(L)][BF4] (L=P(PhPPh 2)3) in the presence of trifluoroacetic acid a broad range of aldehydes are reduced in high yields using low catalyst loadings (0.05-1 mol %). Excellent chemoselectivity for the reduction of aldehydes in the presence of other reducible moieties, for example, ketones, olefins, esters, etc. is achieved. Based on the in situ detected hydride species [FeH(H 2)(L)]+ a catalytic cycle is proposed that is supported by computational calculations. Copyright
- Wienh?fer, Gerrit,Westerhaus, Felix A.,Junge, Kathrin,Ludwig, Ralf,Beller, Matthias
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supporting information
p. 7701 - 7707
(2013/07/11)
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- Rapid synthesis of unsaturated alcohols under mild conditions by highly selective hydrogenation
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Ir-ReOx/SiO2 acted as a highly active and selective heterogeneous catalyst for the hydrogenation of unsaturated aldehydes to unsaturated alcohols in water at low H2 pressure (0.8 MPa) and low temperature (303 K). The catalysis is derived from the synergy between Ir metal and ReOx.
- Tamura, Masazumi,Tokonami, Kensuke,Nakagawa, Yoshinao,Tomishige, Keiichi
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supporting information
p. 7034 - 7036
(2013/09/02)
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- Core-shell AgNP@CeO2 nanocomposite catalyst for highly chemoselective reductions of unsaturated aldehydes
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Selective silver: A core-shell AgNP-CeO2 nanocomposite (AgNP@CeO2) acted as an effective catalyst for the chemoselective reductions of unsaturated aldehydes to unsaturated alcohols with H2 (see figure). Maximizing the AgNP-CeO2 interaction successfully induced the heterolytic cleavage of H2, resulting in highly chemoselective reductions. Furthermore, a highly dispersed AgNP@CeO2 system was also developed that exhibited a higher activity than the original AgNP@CeO2. Copyright
- Mitsudome, Takato,Matoba, Motoshi,Mizugaki, Tomoo,Jitsukawa, Koichiro,Kaneda, Kiyotomi
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supporting information
p. 5255 - 5258
(2013/05/22)
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- Highly efficient reduction of aldehydes with silanes in water catalyzed by silver
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A highly efficient silver-catalyzed chemoselective method for the reduction of aldehydes to their corresponding alcohols in water was developed by using hydrosilanes as reducing agents. The ketones remained essentially inert under the same reaction conditions, thereby providing an additional synthetically useful chemoselectivity. Georg Thieme Verlag Stuttgart, New York.
- Jia, Zhenhua,Liu, Mingxin,Li, Xingshu,Chan, Alberts. C.,Li, Chao-Jun
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p. 2049 - 2056
(2013/10/21)
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- Remarkable effect of bases on core-shell AgNP@CeO2 nanocomposite-catalyzed highly chemoselective reduction of unsaturated aldehydes
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A highly dispersed coreshell silver nanoparticleceria nanocomposite catalyst (AgNP@CeO2-D) was prepared. The addition of bases was found to enhance the catalytic efficiency of AgNP@CeO2-D significantly in the chemoselective reduction of diverse unsaturated aldehydes to the corresponding unsaturated alcohols.
- Mitsudome, Takato,Matoba, Motoshi,Yamamoto, Masaaki,Mizugaki, Tomoo,Jitsukawa, Koichiro,Kaneda, Kiyotomi
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p. 660 - 662
(2013/07/05)
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- Air-stable, nitrile-ligated (cyclopentadienone)iron dicarbonyl compounds as transfer reduction and oxidation catalysts
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A series of air-stable, nitrile-ligated (cyclopentadienone)iron dicarbonyl compounds was synthesized and their activities as catalysts in the transfer reduction of acetophenone were explored. While all were active catalysts, the acetonitrile adduct was chosen for further study and was found to be active in the transfer reduction of aldehydes and ketones and in the Oppenauer-type oxidation of secondary alcohols. The acetonitrile catalyst exhibited activities similar to those of an analogous air-sensitive iron hydride, but unlike the iron hydride it was unreactive in carbonyl reductions using hydrogen gas. Copyright
- Plank, Taylor N.,Drake, Jessica L.,Kim, Daniel K.,Funk, Timothy W.
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supporting information; experimental part
p. 597 - 601
(2012/05/04)
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- α,β-Unsaturated imines via Ru-catalyzed coupling of allylic alcohols and amines
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A convenient synthesis of α,β-unsaturated imines requiring only an allylic alcohol, an amine and a Ru catalyst has been developed. The use of large excesses of oxidant and the purification of sensitive intermediates can be avoided.
- Rigoli, Jared W.,Moyer, Sara A.,Pearce, Simon D.,Schomaker, Jennifer M.
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supporting information; experimental part
p. 1746 - 1749
(2012/04/23)
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- Preparation and utilization of perillyl acetate
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Perillyl acetate is a fragrance compound that was prepared by the reaction of β-pinenoxide with acetic anhydride and using acetic acid as an acid catalyst. Several selected catalysts were tested (homogenous: phosphoric acid, boric acid, acetic acid, and citric acid; heterogeneous: zeolite USY, SSA, and montmorillonite K-10) and the reaction conditions optimized for this reaction. The yield 78.7 % of perillyl acetate was obtained. Mayol (4- isopropylcyclohexylmethanol), a valuable fragrance compound, was further obtained by a two-step synthesis from perillyl acetate. Firstly, perillyl acetate was saponified to perillyl alcohol. The yield of alcohol was 94.4 %. The last step of the entire preparation was the hydrogenation of perillyl alcohol to Mayol. The yield of the desired product of this reaction was 94.6 %. Springer Science+Business Media B.V. 2012.
- ?tekrová, Martina,Paterová-Dudková, Iva,Vysko?ilová-Leitmannová, Eli?ka,?erveny, Libor
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p. 2075 - 2084
(2013/02/22)
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- PHARMACEUTICAL COMPOSITIONS COMPRISING MONOTERPENES
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The present invention provides a process for purifying a monoterpene or sesquiterpene having a purity greater than about 98.5% (w/w) The process comprises the steps of derivatizing the monoterpene (or sesquiterpene) to produce a monoterpene (or sesquiterpene) derivative, separating the monoterpene (or sesquiterpene) derivative, and releasing the monoterpene (or sesquiterpene) from the derivative Also encompassed by the scope of the present invention is a pharmaceutical composition comprising a monoterpene (or sesquiterpene) having a purity greater than about 98.5% (w/w) The purified monoterpene can be used to treat a disease such as cancer The present monoterpene (or sesquiterpene) may be administered alone, or may be co-administered with radiation or other therapeutic agents, such as chemotherapeutic agents.
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Page/Page column 39
(2011/10/03)
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- Radical reactions on pinene-oxide derivatives induced by Ti(III)
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A practical, brief and selective synthesis of several pinene oxide derived terpenoids can be achieved from readily available starting materials. The key step is a radical reaction promoted by titanocene chloride.
- Fernández-Mateos,Herrero Teijón,Rubio González
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supporting information; experimental part
p. 9529 - 9534
(2011/12/15)
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- An Efficient Route to Selective Bio-oxidation Catalysts: an Iterative Approach Comprising Modeling, Diversification, and Screening, Based on CYP102A1
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Perillyl alcohol is the terminal hydroxylation product of the cheap and readily available terpene, limonene. It has high potential as an anti-tumor substance, but is of limited availability. In principle, cytochrome P450 monooxygenases, such as the self-sufficient CYP102A1, are promising catalysts for the oxidation of limonene or other inert hydrocarbons. The wild-type enzyme converts (4R)-limonene to four different oxidation products; however, terminal hydroxylation at the allylic C7 is not observed. Here we describe a generic strategy to engineer this widely used enzyme to hydroxylate exclusively the exposed, but chemically less reactive, primary C7 in the presence of other reactive positions. The approach presented here turns CYP102A1 into a highly selective catalyst with a shifted product spectra by successive rounds of modeling, the design of small focused libraries, and screening. In the first round a minimal CYP102A1 mutant library was rationally designed. It contained variants with improved or strongly shifted regio-, stereo- and chemoselectivity, compared to wild-type. From this library the variant with the highest perillyl alcohol ratio was fine-tuned by two additional rounds of molecular modeling, diversification, and screening. In total only 29 variants needed to be screened to identify the triple mutant A264V/A238V/L437F that converts (4R)-limonene to perillyl alcohol with a selectivity of 97%. Focusing mutagenesis on a small number of relevant positions identified by computational approaches is the key for efficient screening for enzyme selectivity. Successive rounds of modeling (MD simulations of enzyme-substrate complexes to identify hotspots for selectivity), diversification (design of minimal library) and screening of a minimal library is shown to be an efficient approach to shift and maximize regioselectivity of CYP102A1, and thus to generate the valuable oxidation product perillyl alcohol from cheap and readily available limonene.
- Seifert, Alexander,Antonovici, Mihaela,Hauer, Bernhard,Pleiss, Juergen
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experimental part
p. 1346 - 1351
(2012/05/20)
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- Zinc-catalyzed chemoselective reduction of esters to alcohols
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Economical alcohols! A general and chemoselective catalytic reduction of esters to alcohols using inexpensive zinc acetate and silanes has been developed. The operational simplicity and the high functional group tolerance, without the need for protecting and deprotecting steps, make this procedure particularly attractive for organic synthesis. Copyright
- Das, Shoubhik,Moeller, Konstanze,Junge, Kathrin,Beller, Matthias
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experimental part
p. 7414 - 7417
(2011/08/05)
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- Solvent-free chromium catalyzed aerobic oxidation of biomass-based alkenes as a route to valuable fragrance compounds
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Chromium containing mesoporous molecular sieves MCM-41 were shown to be an efficient heterogeneous catalyst for the liquid-phase aerobic oxidation of various monoterpenic alkenes under mild solvent-free conditions. The material was prepared through a direct hydrothermal method and characterized by ICP-AES, N2 adsorption-desorption, TEM, XRD, SAXS, and H2-TPR techniques. Characterizations suggest that chromium introduced in MCM-41 is essentially incorporated in the silica framework, with no extraframework chromium oxides being detected. Various oxygenated monoterpenoids important for the flavor and fragrance industry were obtained with high combined selectivities (75-92%) at 30-40% substrate conversions. The oxidation of β-pinene led almost exclusively to allylic mono-oxygenated derivatives, whereas limonene and α-pinene gave both epoxides and allylic oxidation products. The catalyst undergoes no metal leaching and can be easily recovered and re-used. A silica-included chromium catalyst prepared through a conventional sol-gel method showed activity comparable with that of Cr-MCM-41; however, selectivity was much lower.
- Robles-Dutenhefner, Patricia A.,Brand?o, Bruno B.N.S.,De Sousa, Líniker F.,Gusevskaya, Elena V.
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experimental part
p. 172 - 178
(2012/02/05)
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- METHOD FOR PRODUCING ALCOHOL COMPOUND
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Disclosed is a practical method for efficiently producing an alcohol compound by hydrogenating an aldehyde by using a homogeneous copper catalyst which is an easily-available low-cost metal species. Specifically disclosed is a method for producing an alcohol compound, which is characterized in that a hydrogenation reaction of an aldehyde compound is performed in the presence of a homogeneous copper catalyst and a diphosphine compound.
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Page/Page column 10
(2011/09/14)
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- METHOD FOR PRODUCING ALCOHOL COMPOUND
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Disclosed is a practical method for efficiently producing an alcohol compound by hydrogenating an aldehyde by using a homogeneous copper catalyst which is an easily-available low-cost metal species. Specifically disclosed is a method for producing an alcohol compound, which is characterized in that a hydrogenation reaction of an aldehyde compound is performed in the presence of a homogeneous copper catalyst and a diphosphine compound.
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Page/Page column 13-14
(2011/11/01)
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- METHOD FOR PRODUCING ALCOHOL COMPOUND
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Disclosed is a practical method for efficiently producing an alcohol compound by hydrogenating an aldehyde by using a homogeneous copper catalyst which is an easily-available low-cost metal species. Specifically disclosed is a method for producing an alcohol compound, which is characterized in that a hydrogenation reaction of an aldehyde compound is performed in the presence of a homogeneous copper catalyst, a monophosphine compound and an alcohol selected from the group consisting of primary alcohols, secondary alcohols and mixtures of those.
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Page/Page column 8
(2011/09/14)
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- METHOD FOR PRODUCING ALCOHOL COMPOUND
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Disclosed is a practical method for efficiently producing an alcohol compound by hydrogenating an aldehyde by using a homogeneous copper catalyst which is an easily-available low-cost metal species. Specifically disclosed is a method for producing an alcohol compound, which is characterized in that a hydrogenation reaction of an aldehyde compound is performed in the presence of a homogeneous copper catalyst, a monophosphine compound and an alcohol selected from the group consisting of primary alcohols, secondary alcohols and mixtures of those.
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Page/Page column 11
(2011/10/19)
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- A candidate cDNA clone for (-)-limonene-7-hydroxylase from Perilla frutescens
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Cytochrome P450 mono-oxygenases from peppermint, spearmint and perilla (all members of the family Lamiaceae) mediate the regiospecific hydroxylation of the parent olefin (-)-limonene to produce essential oil components oxygenated at C3, C6 and C7, respectively. Cloning, expression and mutagenesis of cDNAs encoding the peppermint limonene-3-hydroxylase and the spearmint limonene-6-hydroxylase have allowed the identification of a single amino acid residue which determines the regiospecificity of oxygenation by these two enzymes. A hybridization strategy provided a cytochrome P450 limonene hydroxylase cDNA from perilla with which to further evaluate the structural determinants of regiospecificity for oxygenation of the common substrate (-)-limonene. The perilla cDNA was a partial clone of 1550 bp (lacking the N-terminal membrane insertion domain), and shared 66% identity with the peppermint 3-hydroxylase and spearmint 6-hydroxylase at the amino acid level. The perilla cytochrome P450 was expressed in Escherichia coli as a chimeric protein fused with the N-terminal membrane insertion domain of the limonene-3-hydroxylase. The kinetically competent recombinant protein was characterized and shown to produce a mixture of C3-, C6- and C7-hydroxylated limonene derivatives with a distribution of 33%, 14% and 53%, respectively.
- Mau, Christopher J.D.,Karp, Frank,Ito, Michiho,Honda, Gisho,Croteau, Rodney B.
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experimental part
p. 373 - 379
(2010/06/12)
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- Synthesis and AChE inhibitory activity of new chiral tetrahydroacridine analogues from terpenic cyclanones
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This work describes the enantioselective synthesis of a new series of terpenic chiral 9-aminotetrahydroacridine analogues. Several chiral ketones were synthesized from natural monoterpenes in an optically active form and subjected to the cyclodehydration reactions with anthranilonitrile in the presence of BF3·Et2O as catalyst. The 9-aminotetrahydroacridine analogues were tested as acetylcholinesterase (AChE) inhibitors. Based on qualitative structure-activity relationship some trends are suggested.
- Santos Pisoni, Diego dos,Sobieski da Costa, Jessé,Gamba, Douglas,Petzhold, Cesar Liberato,César de Amorim Borges, Antonio,Ceschi, Marco Antonio,Lunardi, Paula,Saraiva Gon?alves, Carlos Alberto
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scheme or table
p. 526 - 535
(2010/04/06)
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- Biomass to chemicals: Rearrangement of β-pinene epoxide into myrtanal with well-defined single-site substituted molecular sieves as reusable solid Lewis-acid catalysts
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The epoxide rearrangement of β-pinene oxide into myrtanal was studied in the presence of solid Lewisacid catalysts. Different metals such as Zr, Sn, Ti, Nb, Ta, Al, and Ga have been incorporated within network positions of zeolite Beta by isomorphous substitution. The materials have been characterized by powdered X-ray diffraction (XRD), IR spectroscopy and by in situ IR spectroscopy on adsorbed molecules (cyclohexanone and pyridine). Among the studied catalysts Zr-Beta gave the best selectivity (up to 94%) in acetonitrile as solvent at practically complete conversion. In this epoxide rearrangement the solvent has to be selected to balance the competitive adsorption of the product. Product desorption is enhanced with acetonitrile which results in a selectivity increase with only a small penalty on the rate of reaction. Zr-Beta has been reused in the batch mode and in a fixed-bed reactor for several times and analysis of the reused catalyst indicated that Zr-Beta is a robust catalyst for the epoxide rearrangement. Leaching of the metal or crystal degradation has not been detected.
- De La Torre, Olalla,Renz, Michael,Corma, Avelino
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experimental part
p. 165 - 171
(2011/10/02)
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- Design of a bio-inspired imidazole-based iron catalyst for epoxidation of olefins: Mechanistic insights
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A novel defined iron catalyst for the epoxidation of aromatic and aliphatic olefins with hydrogen peroxide as the terminal oxidant is described. Our catalyst approach is based on bio-inspired both alkyl- and aryl-substituted imidazoles in combination with cheap and abundant iron trichloride hexahydrate. Heterocycles similar to imidazole can be used as ligands in this epoxidation system, too. The novel system is stable towards air and water. It is shown that the mechanism depends strongly on the used ligands and substrates. In the presence of radical scavengers no carbon-centered radical could be detected.
- Schr?der, Kristin,Junge, Kathrin,Spannenberg, Anke,Beller, Matthias
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experimental part
p. 364 - 370
(2011/01/04)
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- Process for making perillyl alcohol
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A process for making perillyl alcohol is disclosed. The process comprises isomerizing a starting material comprising trans-isocarveol at a temperature within the range of 100° C. to 220° C. in the presence of a Group 5 metal catalyst to produce perillyl alcohol. We surprisingly found that trans-isocarveol, which can be selectively produced from a commercially available mixture of cis- and trans-LMO, can be isomerized directly to perillyl alcohol. Yields of perillyl alcohol are improved when the isomerization is performed under an inert atmosphere and/or in the presence of a phenolic antioxidant. Performing the isomerization in the presence of a high-boiling alcohol and/or distilling the perillyl alcohol product from the reaction mixture in the presence of a high-boiling alcohol, enhances yields and maximizes catalyst use. The resulting distillation residue, which contains recovered Group 5 metal catalyst, is valuable for catalyzing additional trans-isocarveol isomerizations.
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Page/Page column 7
(2010/12/29)
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- Iron-catalyzed epoxidation of aromatic olefins and 1,3-dienes
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The combination of iron(III) chloride, pyridine-2,6-dicarboxylic acid and formamidine ligands allows for the epoxidation of styrenes and conjugated dienes in excellent chemoselectivity and yields.
- Schroeder, Kristin,Enthaler, Stephan,Join, Benoit,Junge, Kathrin,Beller, Matthias
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scheme or table
p. 1771 - 1778
(2010/09/11)
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- Mixed disproportionation versus radical trapping in titanocene(III)-promoted epoxide openings
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The formation of either deoxygenation products or allylic alcohols from epoxides is observed when these substrates are treated with Cp2TiCl under anhydrous conditions. It seems that processes via trisubstituted radicals give allylic alcohols whereas processes via disubstituted radicals may give deoxygenation products or allylic alcohols depending on the structure of the original epoxide. This method allows a controlled access to these functional groups, providing a useful tool in organic synthesis. A mechanistic discussion for these transformations is reported.
- Justicia, José,Jiménez, Tania,Morcillo, Sara P.,Cuerva, Juan M.,Oltra, J. Enrique
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experimental part
p. 10837 - 10841
(2010/02/28)
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- A practical and highly chemoselective hydrogenation of aldehydes with a copper catalyst
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A practical hydrogenation of aldehydes mediated by an inexpensive and easily available base metal, copper, is reported. A copper complex associated with 1,4-bis(diphenylphosphino)butane (DPPB) hydrogenates α,β- unsaturated aldehydes in a highly chemoselective fashion to give allylic alcohols with improved catalytic productivities. The reaction system was also effective for the conversion of simple aldehydes to the corresponding alcohols. Georg Thieme Verlag Stuttgart.
- Shimizu, Hideo,Sayo, Noboru,Saito, Takao
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experimental part
p. 1295 - 1298
(2009/10/24)
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