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Palladium-Catalyzed Reductive Carbonylation of (Hetero) Aryl Halides and Triflates Using Cobalt Carbonyl as CO Source
An efficient protocol for the reductive carbonylation of (hetero) aryl halides and triflates under CO gas-free conditions using Pd/Co2(CO)8 and triethylsilane has been developed. The mild reaction conditions, enhanced chemoselectivity and, easy access to heterocyclic and vinyl carboxaldehydes highlights its importance in organic synthesis.
Dogga, Bhushanarao,Joseph, Jayan T.,Kumar, C. S. Ananda
supporting information
p. 309 - 313
(2020/12/23)

V2O5@TiO2 Catalyzed Green and Selective Oxidation of Alcohols, Alkylbenzenes and Styrenes to Carbonyls
The versatile application of different functional groups such as alcohols (1° and 2°), alkyl arenes, and (aryl)olefins to construct carbon-oxygen bond via oxidation is an area of intense research. Here, we report a reusable heterogeneous V2O5@TiO2 catalyzed selective oxidation of various functionalities utilizing different mild and eco-compatible oxidants under greener reaction conditions. The method was successfully applied for the alcohol oxidation, oxidative scission of styrenes, and benzylic C?H oxidation to their corresponding aldehydes and ketones. The utilization of mild and eco-friendly oxidizing reagents such as K2S2O8, H2O2 (30 % aq.), TBHP (70 % aq.), broad substrate scope, gram-scale synthesis, and catalyst recyclability are notable features of the developed protocol.
Upadhyay, Rahul,Kumar, Shashi,Maurya, Sushil K.
p. 3594 - 3600
(2021/07/02)

SUBSTITUTED-N-HETEROARYL COMPOUNDS AND USES THEREOF
The present disclosure relates generally to compounds useful for the treatment and/or enhancement of cognitive function and negative symptoms associated with central nervous system disorders where the circuitry involving fast spiking PV+ interneurons and the production of cortical gamma oscillations is disrupted. The subject disclosure enables the manufacture of medicaments as well as compositions containing same for use in methods of therapy and prophylaxis of cognitive dysfunction and negative symptoms.
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Page/Page column 76-77

(2020/01/24)

SUBSTITUTED-PYRIDINYL COMPOUNDS AND USES THEREOF
The present application relates generally to compounds useful for the treatment and/or enhancement of cognitive dysfunction and negative symptoms associated with CNS disorders where the circuitry involving fast spiking PV+ interneurons and the production of cortical gamma oscillations is disrupted. The subject disclosure enables the manufacture of medicaments as well as compositions containing same for use in methods of therapy and prophylaxis of cognitive dysfunction and negative symptoms.
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Page/Page column 91

(2020/01/10)

Method for fully synthesizing berberine
The invention discloses a method for fully synthesizing berberine, and relates to a drug synthesis method. The method realizes the industrial full synthesis production of the berberine and is made from a bulk organic raw material catechol, the raw material is easily available, and the price is low; 2,3-dimethoxybenzaldehyde is obtained through selective formylation and methylation of the catechol;after a piperonyl ring is obtained through a catechol methylenenation reaction, piperonyl amine is synthesized through a one-step catalytic addition reaction, so that the synthesis steps of the piperonyl amine are shortened, the use of toxic cyanide is avoided, and the process is green and sustainable; condensation hydrogenation and salification reactions adopt a 'one-pot method', and thus the time and the energy are saved, and the cost is decreased. Industrialized full synthesis production of the berberine opens up large-scale production of the berberine, meets the clinical and research needs of the berberine in current anti-tumor, anti-blood pressure, anti-heart rhythm, blood sugar reduction, treatment of Alzheimer's disease and the like, provides effective drugs for reducing pain of patients, and has remarkable economic and social benefits.
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(2019/04/17)

Method for total synthesis of berberine with guaiacol as raw material
The invention discloses a method for total synthesis of berberine with guaiacol as a raw material. According to a drug synthesis method, guaiacol serves as the raw material, 2-hydroxy-3-methoxybenzaldehyde is obtained through a selective formylation reaction, 2,3-dimethoxybenzaldehyde is obtained through a methylation reaction, pentamethyleneamine is obtained through a methylenenation reaction with catechol as a raw material, and homopiperony lamine is obtained through a one-step catalytic addition reaction; 2,3-dimethoxybenzaldehyde and homopiperony lamine are subjected to a one-pot condensation hydrogenation reaction under the condition of a nickel-based catalyst, hydrochloric acid is added to a reaction product, a crystal substance is cooled, after the reaction product is refined, hydrochloric acid is added, and cooling crystallization and filtration washing are conducted to obtain the product berberine. According to the method, the technology is simplified, and the use of toxic cyanide is avoided; 2,3-dimethoxybenzaldehyde and homopiperony lamine are subjected to a one-pot condensation hydrogenation and salifying technology, the time is saved, the energy is saved, and the costis lowered; in the technological process, solvents are recycled.
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Paragraph 0015

(2019/04/26)

3-INDOLYL FURANOIDS AS INHIBITORS OF MATRIX METALLOPROTEINASE-9 FOR PREVENTION OF GASTRIC ULCER AND OTHER INFLAMMATORY DISEASES
Disclosed are 3-indolyl furanoid compounds which are useful as potent anti-inflammatory agents and prevent gastric ulcer by inhibiting matrix metalloproteinase-9 (MMP-9) expression in gastric mucosal layer. For example, disclosed is a compound of formula 1, wherein: R1 to R6 is selected from H, OH, CH3, OCH3, Br, Cl, Ph or o-OHC6H4, OCH2—CH═CH2, or OCH2CH2CH3, and R1 to R6 is having at least one substituent with alkyl, aryl and heteroaryl groups other than H, wherein the carbon in alkyl, aryl and heteroaryl is in the range of C1 to C8. Various embodiments relate to representative compounds of Formula 1 and method of preparation thereof. Further embodiments relates to the use of representative compounds of Formula 1 in treating diseases associated with gastric ulcer and other inflammatory diseases. A noted feature of an embodiment is the IC50 value of 50 μM of one of the 3-indolyl furanoids.
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Paragraph 0082-0083

(2018/08/29)

Design, synthesis and evaluation of curcumin-based fluorescent probes to detect Aβ fibrils
Amyloid β fibrillation is an early event in Alzheimer's disease, so its detection is important to understand its roles in Alzheimer's disease. Curcumin, which has poor water solubility, has been reported to have many pharmacological activities including potent anti-amyloid β fibril activity in Alzheimer's disease. In this study, we found that curcumin analogues with the fluorescence property instead of non-inhibition of amyloid β fibrils. The development of new curcumin analogue, Me-CUR (9), as fluorescent switchable probe to detect amyloid β fibrils is described. Me-CUR (9) shows excellent fluorescence, especially higher than ThT (4), in the presence of amyloid β fibrils. These results suggest that Me-CUR (9) can become a useful in vitro amyloid fluorescence sensor for diagnosis of Alzheimer's disease.
Sato, Taki,Hotsumi, Mayumi,Makabe, Koki,Konno, Hiroyuki
supporting information
p. 3520 - 3525
(2018/10/15)

Preparation method of 2,3-dimethoxybenzaldehyde
The invention discloses a preparation method of 2,3-dimethoxybenzaldehyde, and belongs to the technical field of medicine techniques. The technical problem to be solved by the invention relates to a more advanced preparation method of 2,3-dimethoxybenzaldehyde. The main point of the technical scheme for solving the technical problem by the invention is an innovative preparation method of the compound.
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Paragraph 0007-0010

(2018/12/03)

Highly Efficient Supramolecular Catalysis by Endowing the Reaction Intermediate with Adaptive Reactivity
A new strategy of highly efficient supramolecular catalysis is developed by endowing the reaction intermediate with adaptive reactivity. The supramolecular catalyst, prepared by host–guest complexation between 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) and cucurbit[7]uril (CB[7]), was used for biphasic oxidation of alcohols. Cationic TEMPO+, the key intermediate, was stabilized by the electrostatic effect of CB[7] in aqueous phase, thus promoting the formation of TEMPO+ and inhibiting side reactions. Moreover, through the migration into the organic phase, TEMPO+ was separated from CB[7] and recovered the high reactivity to drive a fast oxidation of substrates. The adaptive reactivity of TEMPO+ induced an integral optimization of the catalytic cycle and greatly improved the conversion of the reaction. This work highlights the unique advantages of dynamic noncovalent interactions on modulating the activity of reaction intermediates, which may open new horizons for supramolecular catalysis.
Jiao, Yang,Tang, Bohan,Zhang, Yucheng,Xu, Jiang-Fei,Wang, Zhiqiang,Zhang, Xi
supporting information
p. 6077 - 6081
(2018/04/30)

Palladium-Catalyzed Formylation of Aryl Iodides with HCOOH as CO Source
A facile and practical method for the synthesis of aromatic aldehydes by palladium-catalyzed reductive carbonylation starting from aryl iodides and HCOOH is described. Compared to the known formylation procedure, HCOOH serves not only as the most convenient and environmental-friendly C1 source but also as the reviving agent in the reductive elimination process of a Pd-catalyst. Furthermore, this procedure is also applied successfully to the modification of natural products, such as vindoline, tabersonin, and vincamine, to obtain the corresponding products in good yields.
Sun, Guanglong,Lv, Xue,Zhang, Yinan,Lei, Min,Hu, Lihong
supporting information
p. 4235 - 4238
(2017/08/23)

Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
An efficient method for the carbonylation of (hetero) aryl pentafluorobenzenesulfonates and triflates under exceptionally mild conditions using palladium/dicobalt octacarbonyl [Pd/Co2(CO)8] has been developed. Besides acting as carbon monoxide (CO) source, Co2(CO)8enhances the reaction rate by accelerating the CO insertion through an in situ generated bimetallic palladium cobalt tetracarbonyl [Pd-Co(CO)4] complex. Under the optimized reaction condition, carbonylation of a wide range of activated and deactivated, as well as sterically hindered and heteroaromatic, substrates proceeded efficiently at room temperature. The high chemoselectivity and improved synthesis of biologically relevant Isoguvacine and Lazabemide intermediates highlights its scope as a valuable synthetic method. The generality of this protocol was further extended to other electrophiles (bromides, chlorides and tosylates). (Figure presented.).
Joseph, Jayan T.,Sajith, Ayyiliath M.,Ningegowda, Revanna C.,Shashikanth, Sheena
supporting information
p. 419 - 425
(2017/02/10)

Solid state red biphotonic excited emission from small dipolar fluorophores
Dyes emitting in the solid state in the red or near-infrared range are much sought after for application in bioimaging especially if the long emission wavelength can be combined with two-photon excitation to provide unique contrast and penetration depth. In this article we present a series of small push-pull dipolar fluorophores based on 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofurane as electron accepting group. Compounds 1a-1m differ only by the number (one, two or three) and the position of methoxy groups on the electron-donor part. If these compounds are weakly emissive in dilute solution, they exhibit aggregation-induced emission properties and exciting solid state emission in the red - near infrared range very different from one compound to another highlighting the role of the number and of the position of the methoxy electron-donor groups. The solid-state properties were studied by fluorescence spectroscopy and the solid state structures were analyzed by X-ray diffraction showing the presence of a long chain of specific aggregates for the emitting species. Finally, the two-photon excitation properties were measured over the range 780-920 nm directly on the solid.
Ipuy, Martin,Liao, Yuan-Yuan,Jeanneau, Erwann,Baldeck, Patrice L.,Bretonnière, Yann,Andraud, Chantal
supporting information
p. 766 - 779
(2016/02/03)

Diarylmethanes through an Unprecedented Palladium-Catalyzed C-C Cross-Coupling of 1-(Aryl)methoxy-1 H-Benzotriazoles with Arylboronic Acids
1-(Aryl)methoxy-1H-benzotriazoles (ArCH2OBt) are bench-stable reagents that are prepared readily from 1H-benzotriazol-1-yl-4-methylbenzenesulfonate and benzylic alcohols. These compounds, which contain a N-O-C bond, undergo cross-coupling with arylboronic acids by C-O bond scission with catalysts that comprise Pd(OAc)2 and biarylphosphine ligands. Such reactivity of ArCH2OBt derivatives, which lead to diarylmethanes, has not been described previously and constitutes a new activation of benzylic alcohols. With regard to the various ligand-metal complexes that support catalytic activity, it appears that those with smaller "percent buried volumes" (%Vbur) provide better outcomes. This factor has been evaluated in the initial optimization studies and in further reactions with difficult coupling partners. Ligand electronics of the biaryl moiety seem to play a lesser role in this type of reaction. The biscoordinating bis[(2-diphenylphosphino)phenyl] ether appears to be suitable to improve the yields of low-yielding reactions. Phosphine fine: 1-(Aryl)methoxy-1H-benzotriazoles (ArCH2OBt), which contain a N-O-C bond, undergo cross-coupling with arylboronic acids by C-O bond scission with catalysts that comprise Pd(OAc)2 and biarylphosphine ligands. Such reactivity of ArCH2OBt derivatives, which lead to diarylmethanes, has not been described previously and constitutes a new activation of benzylic alcohols.
Singh, Manish K.,Lakshman, Mahesh K.
p. 4156 - 4162
(2016/01/09)

A tris(triazolate) ligand for a highly active and magnetically recoverable palladium catalyst of selective alcohol oxidation using air at atmospheric pressure
High efficiency and selectivity, easy magnetic recovery and recycling, and use of air as the oxidant at atmospheric pressure are major objectives for oxidation catalysis in terms of sustainable and green processes. A tris(triazolyl) ligand, so far only used in copper-catalyzed alkyne azide cycloadditions, was found to be extremely efficient in SiO2/γ-Fe2O3-immobilized palladium complexes. It was characterized by inductively coupled plasma (ICP) analysis, transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectra (XPS) and found to fulfill the combined conditions for the selective oxidation of alcohols to aldehydes and ketones.
Wang, Dong,Deraedt, Christophe,Salmon, Lionel,Labrugère, Christine,Etienne, Laetitia,Ruiz, Jaime,Astruc, Didier
p. 6501 - 6510
(2015/04/22)

Aerobic oxidation of alcohols by using a completely metal-free catalytic system
A metal-free reaction system of air, NH4NO3(cat), 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)(cat), and H +(cat) is introduced as a simple, safe, inexpensive, efficient and chemoselective mediator for aerobic oxidation of various primary and secondary benzyl and alkyl alcohols, including those bearing oxidizable heteroatoms (N, S, O) to the corresponding aldehydes or ketones. Air oxygen under slight overpressure plays the role of the terminal oxidant, which is catalytically activated by redox cycles of nitrogen oxides released from a catalytic amount of NH4NO3 and cocatalyzed by TEMPO (nitroxyl radical compound), under acidic conditions, which are essential for an overall activation of the reaction system. The synthetic value of this reaction system and its green chemical profile was illustrated by a 10 g scale-up experiment, performed in an open-air system by using a renewable and reusable polymer-supported form of TEMPO (OXYNITROXS100). The reaction solvent was recovered by distillation under atmospheric pressure, and the pure final product was isolated under reduced pressure; the acid activators (HCl or H 2SO4) were recovered as ammonium salts. A metal-free reaction system of air/NH4NO3(cat)/TEMPO (cat)/H+(cat) is introduced as a simple, safe, inexpensive, efficient and chemoselective mediator for aerobic oxidation of various primary and secondary benzyl, alkyl and allyl alcohols, including those bearing oxidizable heteroatoms (N, S, O) to the corresponding aldehydes or ketones. Copyright
Prebil, Rok,Stavber, Gaj,Stavber, Stojan
supporting information
p. 395 - 402
(2014/01/23)

Aerobic Oxidation of Alcohols by Using a Completely Metal-Free Catalytic System
A metal-free reaction system of air, NH4NO3(cat), 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)(cat), and H+(cat) is introduced as a simple, safe, inexpensive, efficient and chemoselective mediator for aerobic oxidation of various primary and secondary benzyl and alkyl alcohols, including those bearing oxidizable heteroatoms (N, S, O) to the corresponding aldehydes or ketones. Air oxygen under slight overpressure plays the role of the terminal oxidant, which is catalytically activated by redox cycles of nitrogen oxides released from a catalytic amount of NH4NO3 and cocatalyzed by TEMPO (nitroxyl radical compound), under acidic conditions, which are essential for an overall activation of the reaction system. The synthetic value of this reaction system and its green chemical profile was illustrated by a 10 g scale-up experiment, performed in an open-air system by using a renewable and reusable polymer-supported form of TEMPO (OXYNITROXS100). The reaction solvent was recovered by distillation under atmospheric pressure, and the pure final product was isolated under reduced pressure; the acid activators (HCl or H2SO4) were recovered as ammonium salts.
Prebil, Rok,Stavber, Gaj,Stavber, Stojan
supporting information
p. 395 - 402
(2015/10/05)

Synthesis and properties of bimetallic Hoveyda-Grubbs metathesis catalysts
The catalytic activity of ruthenium Hoveyda-Grubbs complexes in olefin metathesis is a function of complex steric and electronic effects acting on initiation and propagation steps. In order to study the π-electron factors influencing the initiation process, we attempted syntheses of bimetallic complexes with common organic ligands bearing two chelate rings. While most of the studied ligand exchange reactions of the isomeric bis-chelating benzene derivatives gave mixtures of unstable complexes, a homodinuclear derivative of 1,4-dimethoxy-2,5-divinylbenzene was sparingly soluble and precipitated from the reaction mixture in a pure form. The complex was studied with spectroscopic and X-ray methods, which confirmed the symmetrical bimetallic structure. However, in model metathesis reactions the catalyst displayed activity very comparable to the related monometallic complexes. This suggests that in the bimetallic system two consecutive initiation processes of the metathesis catalyst (first, bimetallic complex + olefin → monometallic complex + propagating species; second, monometallic complex + olefin → styrene + propagating species) proceed at similar rates and, thus, no cooperativity between the two steps is displayed. Properties of the family of bimetallic complexes were probed with NMR studies, and π-electronic effects operating in the systems were discussed.
Grudzien, Krzysztof,Malinska, Maura,Barbasiewicz, Michal
scheme or table
p. 3636 - 3646
(2012/07/13)

Copper catalyzed oxidation of benzylic alcohols in water with H 2O2
A straightforward, efficient and sustainable copper catalyzed method was developed for oxidation of benzylic alcohols with 30% H2O2 in water. The reaction proceeded with CuSO4 catalyst (1 mol%) at 100 °C without additional base or ligand. Primary benzylic alcohols were converted almost quantitatively to aldehydes with 70-90% selectivity, corresponding acids being the major side products. Also secondary benzylic alcohols afforded the corresponding ketones in high conversion with selectivities greater than 90%. It was demonstrated that the CuSO4 catalyst can be recycled and reused at least for three runs, even though with some loss of catalytic activity. Selectivity of the CuSO4 based catalyst system could be further increased by using 2-N-(p-fluorophenyl)- pyrrolecarbaldimine (1) as a ligand in combination with TEMPO in K 2CO3 solution. The catalyst system was individually optimized (1 mol% CuSO4, 2 mol% 1, 0.1 M K2CO3 and 5 mol% TEMPO) for a wide range of benzylic and allylic alcohols, which were quantitatively and selectively converted into the corresponding aldehydes with 3 eq. of H2O2 in 1 h.
Ahmad, Jahir Uddin,R?is?nen, Minna T.,Leskel?, Markku,Repo, Timo
experimental part
p. 180 - 187
(2012/02/04)

Room temperature aerobic oxidation of alcohols using CuBr2 with TEMPO and a tetradentate polymer based pyridyl-imine ligand
A series of tetradentate pyridyl-imine terminated Schiff-base ligands has been investigated for their ability in the catalytic oxidation of alcohols when combined with copper bromide (CuBr2) and 2,2,6,6- tetramethylpiperidyl-1-oxy (TEMPO). Analogous bidentate ligands showed poorer catalytic activity and the ratio of Cu:ligand was of crucial importance in maintaining high yields. The polydimethylsiloxane (PDMS) derived pyridyl-imine terminated ligand combined with copper(II) ions affords an effective and selective catalyst for aerobic oxidations of primary and secondary alcohols under aqueous conditions. Preliminary mechanistic studies suggest that bimetallic complexes may be playing a role in the catalytic transformation.
Hu, Zhenzhong,Kerton, Francesca M.
experimental part
p. 332 - 339
(2012/03/26)

Syntheses of differentially protected isocoumarins
Syntheses of an isocoumarin subunit suitable for the completion of purpuromycin are outlined. Specifically, work targeting an orthogonally protected isocoumarin (eventually 12% yield over 12 steps) and an improved synthesis of a symmetrically protected isocoumarin (18% over 10 steps) are described. A new modification for selective catechol protection as mediated by potassium bicarbonate is also presented along with insights into oxidative and reductive functionalization of isocoumarins.
Lowell, Andrew N.,Wall, Philip D.,Waters, Stephen P.,Kozlowski, Marisa C.
experimental part
p. 5573 - 5582
(2010/10/01)

Solvent-free oxidation of alcohols with potassium persulphate in the presence of bronsted acidic ionic liquids
An efficient conversion of alcohols to aldehydes was achieved using potassium persulphate and 3-methylimidazolinium methane sulfonate. Copyright Taylor & Francis Group, LLC.
Chaskar,Bhandari,Patil,Sharma,Mayeker
experimental part
p. 366 - 370
(2009/04/07)

Palladium-catalyzed aerobic alcohol oxidation supported by a new type of α-diimine ligands
A series of new ionic sulfonated α-diimine ligands were prepared and employed as supporting ligands for the palladium-catalyzed aerobic alcohol oxidation. The electronic properties, rigidity, and steric hindrance of ligands have remarkable influences upon the catalytic activity of the palladium complexes. The best catalytic result could be achieved using ligand 9 with an electron-withdrawing sulfonyl substituent together with bulky groups (iso-propyl in 2,6-positions). This diimine/palladium-catalyzed system is highly efficient for the oxidation of various benzylic alcohols, and showed moderate yields for the secondary aliphatic alcohols and cyclic alcohols.
Zhou, Jin,Li, Xiaoyan,Sun, Hongjian
p. 782 - 790
(2008/12/20)

Arylalkylamine vanadium (V) salts for the treatment and/or prevention of Diabetes mellitus
This invention provides compounds of formula (IIA) and pharmaceutical compositions thereof, where M, a, b, and R1-R5 are as defined herein, for treating human type 1 and type 2 diabetes, particularly insulin-resistant diabetes. Pharmaceutical compositions comprising the compounds of formula (IIA) are also disclosed.
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Page/Page column 17

(2010/11/26)

ARYLALKYLAMINE VANADIUM (V) SALTS FOR THE TREATMENT AND/OR PREVENTION OF DIABETES MELLITUS
This invention provides compounds and pharmaceutical compositions thereof for treating human type 1 and type 2 diabetes, particularly insulin-resistant diabetes.
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Page/Page column 43-44

(2010/02/15)

COMPOSITION OF SSAO SUBSTRATES AND METAL COMPOUNDS OF THE VLA AND VLB GROUPS OF THE PERIODIC TABLE
This invention relates to (pharmaceutical) compositions comprising a combination of SSAO substrates and pharmaceutically acceptable compounds of the Vla and Vlb group of the periodic table, i.e. selenium (VI)-, molybdenum (VI)- and tungsten (V)/(VI) compounds, etc. and to their use as insulin mimetic, i.e., to treat illness Diabetes mellitus, Obesity, or their symptoms. A here discovered synergism between the compounds of the Vla and Vlb groups of the periodic table, i.e. selenium (VI)-, molybdenum (VI)- and tungsten (V)/(VI) com-pounds, etc. and the SSAO substrates makes the effective concentration of the compounds of the Via and Vlb groups of the periodic table in the (pharmaceutical) composition one order of magnitude lower than the corresponding compound of the Vla and Vlb groups alone. Consequently the inventive (pharmaceutical) composition has much lower toxicity than the known compounds or compositions in the art alone, what is a crucial advantage of the former for its use in the treatment and/or prevention of Diabetes mellitus, particularly of Diabetes type 2, or Obesity.
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Page/Page column 25

(2010/11/08)

Synthesis and new rearrangements of 4-isoxazolin-4,5-dicarboxylic acid derivatives
Acyclic nitrones react with dimethyl acetylenedicarboxylate (DMAD) to give stable isoxazolines, from which the ones that contain electron-donating aromatic rings at the C3 position (R1) were shown to undergo unprecedented fragmentation at room temperature, giving the R1-aldehyde and inseparable product mixtures, probably due to the formation of highly reactive species such as iminocarbenes. Attempts to convert the isoxazolines to the corresponding stable azomethine ylides, by refluxing in toluene, again led to the same product mixtures as above (e.g., the room temperature decomposition). Isoxazolines when reacted with methoxide at room temperature afforded highly functionalised diastereomeric mixtures. Also, isoxazolines, when reacted with propylamine, gave the corresponding amides regioselectively, all of which were more stable than the parent isoxazolines.
Co?kun, Necdet,?ztürk, Aylin
p. 12057 - 12063
(2007/10/03)

Oxidation of alcohols with 1-decyl-4-aza-1-azonia-bicyclo[2.2.2]-octane chlorochromate under conventional and solvent-free conditions
1-Decyl-4-aza-1-azoniabicyclo[2.2.2]octane chlorochromate was proposed as a mild and efficient reagent for oxidation of alcohols to the corresponding carbonyl compounds in boiling acetonitrile or under solvent-free conditions at room temperature. The experimental procedure is simple, and the products are isolated in good to excellent yields. Pleiades Publishing, Inc., 2006.
Hajipour,Bagheri,Ruoho
p. 844 - 848
(2007/10/03)

Nitric acid in the presence of supported P2O5 on silica gel affords an efficient and mild system for oxidation of organic compounds under solvent-free conditions
This paper describes an efficient and easy method for oxidation of alcohols 1 and sulfides 2 to their corresponding carbonyl compounds 3 and sulfoxides 4 with nitric acid in the presence of supported P2O5 on silica gel under solvent-free conditions in high yields.
Hajipour, Abdol R.,Guo, Lian-Wang,Ruoho, Arnold E.
p. 85 - 93
(2008/02/04)

Oxidation of alcohols with 1-butyl-4-aza-1-azoniabicyclo[2.2.2]octane chlorochromate (BAAOCC) under non-aqueous conditions
1-Butyl-4-aza-1-azoniabicyclo[2.2.2]octane chlorochromate (BAAOC) in the presence of AlCl3 affords an efficient and mild system for oxidation of a variety of alcohols, giving the corresponding aldehydes and ketones in refluxing acetonitrile. The experimental procedure is simple and the products are isolated straightforward in good to excellent yields.
Hajipour, Abdol R.,Bagheri, Hamid R.,Ruoho, Arnold E.
p. 577 - 580
(2007/10/03)

Kinetics of oxidation of benzyl alcohols by the dication and radical cation of ABTS. Comparison with laccase-ABTS oxidations: An apparent paradox
Laccase, a blue copper oxidase, in view of its moderate redox potential can oxidise only phenolic compounds by electron-transfer. However, in the presence of ABTS (2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonate) as a redox mediator, laccase reacts with the more difficult to oxidise non-phenolic substrates, such as benzyl alcohols. The role of ABTS in these mediated oxidations is investigated. Redox interaction with laccase could produce in situ two reactive intermediates from ABTS, namely ABTS++ or ABTS ?+. These species have been independently generated by oxidation with Ce(IV) or Co(III) salts, respectively, and their efficiency as monoelectronic oxidants tested in a kinetic study towards a series of non-phenolic substrates; a Marcus treatment is provided in the case of ABTS ++. On these grounds, intervention of ABTS++ as a reactive intermediate in laccase-ABTS oxidations appears unlikely, because the experimental conditions under which ABTS++ is unambiguously generated, and survives long enough to serve as a diffusible mediator, are too harsh (2 M H2SO4 solution) and incompatible with the operation of the enzyme. Likewise, ABTS?+ seems an intermediate of limited importance in laccase-ABTS oxidations, because this weaker monoelectronic oxidant is unable to react directly with many of the non-phenolic substrates that laccase-ABTS can oxidise. To solve this paradox, it is alternatively suggested that degradation by-products of either ABTS ++ or ABTS?+ are formed in situ by hydrolysis during the laccase-ABTS reactions, and may be responsible for the observed oxidation of non-phenolics. The Royal Society of Chemistry 2005.
Branchi, Barbara,Galli, Carlo,Gentili, Patrizia
p. 2604 - 2614
(2007/10/03)

Compositions containing aromatic aldehydes and their use in treatments
Disclosed are pharmaceutical and cosmetic compositions containing aromatic aldehyde compounds. Some of the disclosed compositions are useful as topical therapeutics for treating inflammatory dermatologic conditions. Some of the compositions are useful in transdermal and other systemic dose forms for treating other inflammatory conditions in mammals.
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(2008/06/13)

An efficient catalytic deprotection of thioacetals employing bismuth triflate: Synthesis of pyrrolo[2,1-c] [1,4] benzodiazepines
A simple and efficient deprotection of thioacetals has been achieved by employing bismuth triflate. This method has been effectively employed in the preparation of DNA-binding pyrrolo[2,1-c] [1,4]benzodiazepine and its dimers.
Kamal, Ahmed,Reddy,Reddy, D. Rajasekhar
p. 2857 - 2860
(2007/10/03)

Oxidation of alcohols with butyltriphenylphosphonium periodate under non-aqueous conditions
The combination of butyltriphenylphosphonium periodate (BUTPPPI) and aluminum chloride in refluxing acetonitrile affords an efficient and mild system for the oxidation of a variety of alcohols, to the corresponding aldehydes and ketones. The experimental procedure is simple and the products are easily isolated in good yields.
Hajipour, Abdol R.,Mallakpour, Shadpour E.,Samimi, Heshmat A.
p. 270 - 271
(2007/10/03)

A synthesis of the phenolic lipid, 3-[(Z)-pentadec-8-enyl] catechol, (15:1)-urushiol
A synthesis of (15:1)-urushiol, urushiol monoene, 3-[(Z)-pentadec-8-enyl] catechol, 1,2-dihydroxy-3-[(Z)-pentadec-8-enyl] benzene, one of the toxic principles of Rhus toxicodendron and of Rhus vernicifera is described. 6-Chlorohexan-1-ol protected at the OH group with ethyl vinyl ether reacted with 2,3-dimethoxybenzaldehyde in the presence of lithium to give, after removal of the protective group with methanolic 4-toluenesulphonic acid, 1-(2,3-dimethoxyphenyl) heptane-1,7-diol. Catalytic hydrogenolysis in ethanol with palladium-carbon selectively afforded 7-(2,3-dimethoxyphenyl)heptane-1-ol accompanied by a small proportion of the 7-(3-methoxyphenyl)heptane-1-diol, formed by demethoxylation. Reaction of the dimethoxy compound with boron tribromide resulted in both bromination and demethylation to give 7-(2,3-dihydroxyphenyl) heptylbromide. This bromide in tetrahydrofuran (THF) containing hexamethylphosphoric triamide reacted with excess lithium oct-1-yne to give 3-(pentadec-8-enyl)catechol which, by catalytic hydrogenation in ethyl acetate containing quinoline, selectively formed the required cis product, 3-[(Z)-pentadec-8-enyl]catechol which was identical chromatographically and spectroscopically with urushiol monoene separated from the natural product.
Tyman, John H. P.,Schofield, Brian G.,Khor, Choong H.
p. 101 - 108
(2007/10/03)

Organic reactions under solid-state conditions
Manipulatively simple and rapid methods are described for the synthesis of: chiral sulfinate esters from sulfonyl chlorides and sufonic acids; aldehydes and ketones from oximes, alcohols, hydrozones; sulfoxides from sulfides; and disulfides from thiols. The chemical yields are good to excellent and diastereoselectivity is high.
Hajipour,Mallakpour
p. 371 - 387
(2007/10/03)

Silica gel supported jones reagent (SJR): A simple and efficient reagent for oxidation of benzyl alcohols to benzaldehydes
Jones reagent supported on silica gel (SJR) has been used for oxidation of benzyl alcohols to the corresponding benzaldehydes in high yields utilizing organic solvent. This newly developed reagent is easy to prepare and use. SJR is also safer than the traditional Jones reagent.
Ali,Wiggin
p. 1389 - 1397
(2007/10/03)

Design and synthesis of 99mTc-labeled benzamides dopamine D2/D3 receptor imaging agents
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Jia, F.,Liu, B. L.,Liu, Z. H.
p. S547 - S549
(2007/10/03)

Benzyltriphenylphosphonium chlorochromate: A mild and novel reagent for oxidation of benzylic and allylic alcohols under non-aqueous and aprotic conditions or microwave conditions
This paper describes the oxidation of benzylic and allylic alcohols under non-aqueous and aprotic conditions or microwave conditions using benzyltriphenylphosphonium chlorochromate (1) PhCH2PPh3CrO3.HCl which has been prepared by mixing an aqueous solution of benzyltriphenylphosphonium chloride with CrO3 in 6 N HCl at room temperature. This reagent is stable orange powder which may be stored for months without loss of its activity. This compound is readily soluble in organic solvents such as acetonitrile, chloroform and dichloromethane and slightly soluble in carbon tetrachloride, ether and hexane, the oxidation under microwave conditions is much more faster.
Hajipour,Mallakpour,Backnejad
p. 3855 - 3864
(2007/10/03)

Solid-phase oxidation of organic compounds with benzyltriphenylphosphonium dichromate
Benzyltriphenylphosphonium dichromate could be used for oxidation of organic compounds such as alcohols, thiols and sulfides to the corresponding carbonyl, disulfide and sulfoxide derivatives under solid-phase conditions. This reagent is very easily prepared from an aqueous solution of benzyltriphenylphosphonium chloride with CrO3 in 3 N HCl at room temperature. The reagent, is a stable orange powder, which may be stored for month without loss of its activity.
Hajipour,Mohammadpoor-Baltork, Iraj
p. 145 - 151
(2007/10/03)

Oxidation of alcohols with benzyltriphenylphosphonium peroxymonosulfate under non-aqueous conditions
Oxidation of allylic and benzylic alcohols with benzyltriphenylphosphonium peroxymonosulfate (PhCH2Ph3P+HSO5-) 1 (BTPPMS) in refluxing acetonitrile is reported. The oxidation in the presence of a catalytic amount of bismuth chloride enhances the rate.
Hajipour,Mallakpour,Adibi
p. 71 - 79
(2007/10/03)

Benzyltriphenylphosphonium peroxymonosulfate: As a novel and efficient reagent for oxidation of alcohols under solvent-free conditions
This paper describes the oxidation of alcohols under solvent-free conditions using benzyltriphenylphosphonium peroxymonosulfate, which has been prepared by mixing an aqueous solution of benzyltriphenylphosphonium chloride with oxone at room temperature. This reagent is stable white powder, which may be stored for months without loss of its activity. This compound is readily soluble in organic solvents such as acetonitrile, chloroform, and dichloromethane and slightly soluble in carbon tetrachloride, ether, and hexane.
Hajipour, Abdol Reza,Mallakpour, Shadpour E.,Adibi, Hadi
p. 460 - 461
(2007/10/03)

Benzyltriphenylphosphonium dichromate as a mild reagent for the oxidation of organic compounds
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Hajipour, Abdol Reza,Mohammadpoor-Baltork, Iraj,Niknam, Kurosh
p. 335 - 341
(2007/10/03)

Oxidation of alcohols to carbonyl compounds under solvent-free conditions using permanganate supported on alumina
A manupulatively simple and rapid method for oxidation of alcohols to the corresponding carbonyl compounds is described. The reaction is conduced under solventless 'dry' conditions using alumina-supported permanganate.
Hajipour, Abdol Reza,Mallakpour, Shadpour E.,Imanzadeh, Gholamhasan
p. 99 - 100
(2007/10/03)

An easy and efficient method for oxidation of alcohols and aromatic amines to the corresponding carbonyl and azo compounds under non-aqueous and neutral conditions
1-Benzyl-1-aza-4-azoniabicyclooctane periodate 1, readily prepared as an orange solid from commercially available 1,4-diazobicyclooctane, is useful for oxidation in anhydrous conditions.The reagent converts alcohols to die corresponding carbonyl compounds, α hydroxy ketones to diketones, and aromatic amines to azo compounds, in me excellent yields.The reagent ineffective in oxidising double bonds, aldehydes and ketones.
Hajipour, A. R.,Mahboobkhah, N.
p. 285 - 287
(2007/10/03)

Bis(1-benzyl-4-aza-1-azoniabicyclo[2.2.2]octane) peroxodisulfate: A mild and efficient oxidant for cleavage of nitrogen double bonds and oxidation of alcohols under anhydrous conditions
Bis(1-benzyl-4-aza-1-azoniabicyclo[2.2.2]octane) peroxodisulfate (1), is readily prepared as an orange solid from commercially available 1,4- diazabicyclo[2.2.2]octane and potassium peroxodisulfate. This reagent easily converts hydrazones, semicarbazones, oximes, and alcohols to the corresponding carbonyl compounds with excellent yields.
Hajipour, Abdol Reza,Baltork, Iraj Mohammadpoor,Kianfar, Godaraz
p. 2655 - 2659
(2007/10/03)

One pot conversion of carboxylic acids to aldehydes with DIBAL-H
A mild and selective reduction of carboxylic acids to aldehydes is described. This process involves in situ protection of carboxylic acid as its TMS ester which was reduced to aldehyde using stoichiometric amounts of DIBAL-H.
Chandrasekhar,Kumar, M. Suresh,Muralidhar
p. 909 - 910
(2007/10/03)

Process for nucleophilic fluoroalkylation of aldehydes
Aryl difluoromethyl sulfone adds to alkehydes under phase transfer conditions to give novel substituted alcohols of the general formula wherein R is an aryl, cycloaliphatic, sec- or tert-aliphatic, or heterocyclic group and Ar is an aryl group. The substituted alcohols of formula I are of particular utility as intermediates in the synthesis of a variety of useful end products. For example, the products of formula I may be utilized in desulfonylation reactions, oxidation reactions and fluorination reactions.
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(2008/06/13)

3-METHOXYBENZYL (3-MPM) AND 3,5-DIMETHOXYBENZYL (3,5-DMPM) PROTECTING GROUPS FOR THE HYDROXY FUCTION LESS READILY REMOVABLE THAN 4-METHOXYBENZYL (MPM) AND 3,4-DIMETHOXYBENZYL (DMPM) PROTECTING GROUPS BY DDQ OXIDATION
New protecting groups for the hydroxy fuction, 3-methoxybenzyl (3-MPM) and 3,5-dimethoxybenzyl (3,5-DMPM) groups are slowly removed by DDQ oxidation at room temperature and distinguished from readily removable 4-methoxybenzyl (MPM).They are stable to strong acids.KEYWORDS-- protecting group; hydroxy function; DDQ oxidation; selective deprotection; 3-methoxybenzyl; 3,5-dimethoxybenzyl
Nakajima, Noriyuki,Abe, Reiko,Yonemitsu, Osamu
p. 4244 - 4247
(2007/10/02)

3-(substituted phenyl)phthalides
Process comprises the combination of the three steps of condensing 3-N(R)2 -4-X-benzoic acid with an aromatic or heterocyclic aldehyde, Y-CHO, under acidic conditions to produce 3-Y-5-X-6-N(R)2 phthalide (II), condensing said phthalide with a compound of the formula Z-H under alkaline or acid conditions to produce 2-(α-Y-α-Z)methyl-4-X-5-N(R)2 benzoic acid (III), and oxidizing said benzoic acid to produce 3-Y-3-Z-5-X-6-N(R)2 phthalide (I) where: R is hydrogen, non-tertiary alkyl of one to four carbon atoms, benzyl or substituted benzyl; X is hydrogen or halo; Y is 4-R1 -3-R2 -2-R1 -phenyl, 1-R5 -2-R6 -5/6-R4 -3-indolyl, 9-R7 -3-carbazolyl, 9-julolidinyl, 3,4-dioxymethylenephenyl, 2-thienyl, 1-R8 -2-pyrrolyl, or 4-pyridinyl; and Z is 4-R1 -3-R2 -2-R1 -phenyl, 1-R5 -2-R6 -5/6-R4 -3-indolyl or 1-R8 -2-pyrrolyl which are useful as colorless precursor color formers in carbonless duplicating and in thermal marking systems. The intermediates, 3-Y-5-X-6-N(R)2 phthalides (II) and 2-(α-Y-α-Z)methyl-4-X-5-N(R)2 benzoic acids (III) also have utility as colorless precursor color formers in carbonless duplicating and thermal marking systems.
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(2008/06/13)