cas 5022-29-7, N-ETHYLPHTHALIMIDE | Articles data

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Preparation method of N-alkyl phthalimide
The invention discloses a preparation method of N-alkyl phthalimide. The method comprises the steps: taking phthalic anhydride as a raw material, taking an aqueous solution of alkylamine as an imidization reagent ( no other reagents do not need to be added), and directly synthesizing the N-alkyl phthalimide, wherein the yield is high (96% or above), and the purity is high (99% or above). The preparation method is loose in reaction condition, simple in step and easy to implement; no organic solvent is needed, no other substances are discharged except water, and the method is green, free of pollution and suitable for industrial production.
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Paragraph 0035-0036

(2021/03/13)

Preparation method of N - alkyl -4 -nitrophthalimide
The invention discloses a preparation method of N - alkyl -4 -nitrophthalimide, which comprises the following steps of 1) mixing phthalic anhydride, alkyl aldehyde and inorganic amine, reacting under the action of hydrogen, cooling and crystallizing, and drying to obtain N -alkyl phthalimide. Step 2) The 1 alkylphthalimide obtained in step N -) is subjected to nitration reaction, and the product is purified and dried to obtain the N -alkyl -4 -nitrophthalimide. The alkyl aldehyde in step 1) is preferably an alkyl aldehyde of carbon 1 - 4. The preparation method has the advantages of wide raw material source, low price, simple process, easiness in large-scale production and the like. Through one-step synthesis, the reaction efficiency is high, the device is simple and easy to operate, and green and environment-friendly.
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Paragraph 0043-0044

(2021/10/27)

Binuclear Pd(I)-Pd(I) Catalysis Assisted by Iodide Ligands for Selective Hydroformylation of Alkenes and Alkynes
Since its discovery in 1938, hydroformylation has been thoroughly investigated and broadly applied in industry (>107 metric ton yearly). However, the ability to precisely control its regioselectivity with well-established Rh- or Co-catalysts has thus far proven elusive, thereby limiting access to many synthetically valuable aldehydes. Pd-catalysts represent an appealing alternative, yet their use remains sparse due to undesired side-processes. Here, we report a highly selective and exceptionally active catalyst system that is driven by a novel activation strategy and features a unique Pd(I)-Pd(I) mechanism, involving an iodide-assisted binuclear step to release the product. This method enables β-selective hydroformylation of a large range of alkenes and alkynes, including sensitive starting materials. Its utility is demonstrated in the synthesis of antiobesity drug Rimonabant and anti-HIV agent PNU-32945. In a broader context, the new mechanistic understanding enables the development of other carbonylation reactions of high importance to chemical industry.
Zhang, Yang,Torker, Sebastian,Sigrist, Michel,Bregovi?, Nikola,Dydio, Pawe?
supporting information
p. 18251 - 18265
(2020/11/02)

Synthesis, molecular docking, cytotoxicity and antioxidant activity evaluation of isoindoline-1,3-dione derivatives
A variety of amines have been employed to functionalize isobenzofuran-1,3-dione to obtain isoindoline-1,3-dione derivatives in the base free conditions. All the synthesized compounds are screened for their bioactivity through molecular docking, cytotoxicity (against HeLa) and antioxidant activity. ABTS and DPPH are employed to assess the antioxidant activity. Among the synthesized isoindoline-1,3-dione derivatives (3a-k), compound 3e has showed the best antioxidant activity and also exhibited better binding energy when docked with caspase-3 protein. Cytotoxicity of the synthesized compounds was studied against cervical cancer cell line (HeLa) and compound 3e has displayed better activity than other isoindoline derivatives.
Kumar, Palanichamy Santhosh,Kumar, Kuruba Bharath,Obadiah, Asir,Kumar, Suluvoy Jagadish,Mohanapriya, Raman,Durairaj, Arulappan,Ramanathan, Subramanian,Vasanthkumar, Samuel
p. 2548 - 2556
(2019/10/02)

DIELS- ALDER RING-OPENING PROCESS
The invention is directed to a process for the ring-opening of a cycloadduct of formula I obtainable from a reaction of a furanic compound and a diene, said process comprising contacting the cycloadduct with an acidic mixture comprising sulfuric acid and an activating agent to obtain a ring-opened product. The present invention is particularly directed a continuous process.
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Page/Page column 20

(2019/11/19)

Microwave-assisted synthesis method for ethylation reaction
The invention relates to a microwave-assisted synthesis method for an ethylation reaction. The method is characterized in that a reaction substrate is in an organic solvent, trifluoroacetic acid ethyl ester is taken as an ethylation reagent, in the presence of an alkali, microwave-assisted heating is carried out for 2 minutes, and a corresponding ethylation product can be obtained. The invention provides a new method for the ethylation reaction. The reaction rate of the method is several times higher than that of a traditional method, the operation is simple and convenient, the cost is low, the reaction time is short, the application range of the substrate is wide, the use of the expensive or hypertoxic ethylation reagent can also be avoided, and the method has higher application value.
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Paragraph 0012

(2019/10/05)

Normal Alpha Olefin Synthesis Using Dehydroformylation or Dehydroxymethylation
The present invention discloses processes for producing normal alpha olefins, such as 1-hexene, 1-octene, 1-decene, and 1-dodecene in a multistep synthesis scheme from another normal alpha olefin. Also disclosed are reactions for converting aldehydes, primary alcohols, and terminal vicinal diols into normal alpha olefins.
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Paragraph 0127; 0128; 0129

(2019/09/06)

Oxidative Dehydroxymethylation of Alcohols to Produce Olefins
Catalyst compositions for the conversion of aldehyde compounds and primary alcohol compounds to olefins are disclosed herein. Reactions include oxidative dehydroxymethylation processes and oxidative dehydroformylation methods, which are beneficially conducted in the presence of a sacrificial acceptor of H2 gas, such as N,N-dimethylacrylamide.
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Paragraph 0058

(2019/09/06)

PPh3/I2/HCOOH: An efficient CO source for the synthesis of phthalimides
A straightforward and general method has been developed for the synthesis of phthalimide derivatives from 2-iodobenzamides and PPh3/I2/HCOOH in the presence of a catalytic amount of Pd(OAc)2. The reaction results demonstrate that PPh3/I2/HCOOH is a facile, efficient and safe CO source. The whole process is carried out in toluene at 80 °C and furnishes the desired products in good to excellent yields.
Wang, Yingying,Zhou, Yang,Lei, Min,Hou, Jinjun,Jin, Qinghao,Guo, Dean,Wu, Wanying
supporting information
p. 1180 - 1185
(2019/01/26)

Biomolecule-derived supported cobalt nanoparticles for hydrogenation of industrial olefins, natural oils and more in water
Catalytic hydrogenation of olefins using noble metal catalysts or pyrophoric RANEY nickel is of high importance in the chemical industry. From the point of view of green and sustainable chemistry, design and development of Earth-abundant, less toxic, and more environmentally friendly catalysts are highly desirable. Herein, we report the convenient preparation of active cobalt catalysts and their application in hydrogenations of a wide range of terminal and internal carbon-carbon double bonds in water under mild conditions. Catalysts are prepared on multi-gram scale by pyrolysis of cobalt acetate and uracil, guanine, adenine or l-tryptophan. The most active material Co-Ura/C-600 showed good productivity in industrially relevant hydrogenation of diisobutene to isooctane and in natural oil hardening.
Pews-Davtyan, Anahit,Scharnagl, Florian Korbinian,Hertrich, Maximilian Franz,Kreyenschulte, Carsten,Bartling, Stephan,Lund, Henrik,Jackstell, Ralf,Beller, Matthias
supporting information
p. 5104 - 5112
(2019/09/30)

Synthetic method of industrial additive N-ethyl phthalimide
The invention discloses a synthetic method of industrial additive N-ethyl phthalimide. The synthetic method includes the steps: taking phthalimide and ethylene as main reaction substrates to perform free radical addition reaction under the condition of an initiator to obtain the N-ethyl phthalimide. The molar ratio of the phthalimide to the ethylene in a reaction system is 1:1-1:3, the initiator is an organic peroxide, the dosage of the organic peroxide initiator accounts for 5-10% of the weight of the phthalimide, reaction temperature ranges from 50 DEG C to 100 DEG C, and reaction time ranges from 3 hours to 5 hours. According to the method, the used phthalimide and the used ethylene are low in cost and easy to get, and the method has the advantages of mild reaction condition and low production cost.
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Paragraph 0032-0038; 0040; 0041; 0042; 0044-0046

(2018/10/19)

Tandem Catalysis: Transforming Alcohols to Alkenes by Oxidative Dehydroxymethylation
We report a Rh-catalyst for accessing olefins from primary alcohols by a C-C bond cleavage that results in dehomologation. This functional group interconversion proceeds by an oxidation-dehydroformylation enabled by N,N-dimethylacrylamide as a sacrificial acceptor of hydrogen gas. Alcohols with diverse functionality and structure undergo oxidative dehydroxymethylation to access the corresponding olefins. Our catalyst protocol enables a two-step semisynthesis of (+)-yohimbenone and dehomologation of feedstock olefins.
Wu, Xuesong,Cruz, Faben A.,Lu, Alexander,Dong, Vy M.
supporting information
p. 10126 - 10130
(2018/08/23)

Dual Rh?Ru Catalysts for Reductive Hydroformylation of Olefins to Alcohols
An active and selective dual catalytic system to promote domino hydroformylation–reduction reactions is described. Apart from terminal, di- and trisubstituted olefins, for the first time the less active internal C?C double bond of tetrasubstituted alkenes can also be utilized. As an example, 2,3-dimethylbut-2-ene is converted into the corresponding n-alcohol with high yield (90 %) as well as regio- and chemoselectivity (>97 %). Key for this development is the use of a combination of Rh complexes with bulky monophosphite ligands and the Ru-based Shvo's complex. A variety of aromatic and aliphatic alkenes can be directly used to obtain mainly linear alcohols.
Rodrigues, Fábio M. S.,Kucmierczyk, Peter K.,Pineiro, Marta,Jackstell, Ralf,Franke, Robert,Pereira, Mariette M.,Beller, Matthias
p. 2310 - 2314
(2018/07/31)

Visible-Light-Mediated Efficient Metal-Free Catalyst for α-Oxygenation of Tertiary Amines to Amides
A metal-free system has been discovered for the efficient α-oxygenation of tertiary amines to the corresponding amides using oxygen as an oxidant. This visible-light-mediated oxygenation reaction exhibited excellent substrates scope under mild reaction conditions and generated water as the only byproduct. The synthetic utility of this approach has been demonstrated by applying onto drug molecules. At the end, detailed mechanistic reactions clearly showed the role of oxygen and the photocatalyst.
Zhang, Yu,Riemer, Daniel,Schilling, Waldemar,Kollmann, Jiri,Das, Shoubhik
p. 6659 - 6664
(2018/06/25)

Mechanochemical N-alkylation of imides
The mechanochemical N-alkylation of imide derivatives was studied. Reactions under solvent-free conditions in a ball mill gave good yields and could be put in place of the classical solution conditions. The method is general and can be applied to various imides and alkyl halides. Phthalimides prepared under ball milling conditions were used in a mechanochemical Gabriel synthesis of amines by their reaction with 1,2-diaminoethane.
Bri?, Anamarija,Dud, Mateja,Margeti?, Davor
supporting information
p. 1745 - 1752
(2017/09/27)

Application of Pd Nanoparticles Supported on Mesoporous Hollow Silica Nanospheres for the Efficient and Selective Semihydrogenation of Alkynes
Herein, the preparation of a heterogeneous catalyst consisting of 1-2 nm sized Pd nanoparticles supported on amino-functionalized mesoporous hollow silica nanospheres and its use for the semihydrogenation of mono- And disubstituted alkynes is reported. By utilizing this Pd nanocatalyst together with the green poisoning agent DMSO, high yields of the desired alkenes could be achieved, while suppressing the degree of over-reduction to alkanes. To our delight, the Pd nanocatalyst displayed remarkable chemoselectivity towards the alkyne moiety, allowing the transformation to be carried out in the presence of other reducible functionalities, such as halogens, carbonyl, and nitro groups.
Verho, Oscar,Zheng, Haoquan,Gustafson, Karl P. J.,Nagendiran, Anuja,Zou, Xiaodong,B?ckvall, Jan-E.
p. 773 - 778
(2016/03/05)

Zinc-catalyzed selective reduction of cyclic imides with hydrosilanes: Synthesis of ω-hydroxylactams
Cyclic imides were selectively reduced to the corresponding ω-hydroxylactams in high yields with (EtO)3SiH (triethoxysilane) or PMHS (polymethylhydrosiloxane) under catalysis of zinc diacetate dehydrate [Zn(OAc)2 2H2O] (10%) and tetramethylethylenediamine (TMEDA) (10%). This catalytic protocol showed good functional group tolerance as well as excellent regioselectivity for unsymmetrical imides bearing coordinating groups adjacent to the carbonyl.
Ding, Guangni,Lu, Bin,Li, Yuyuan,Wan, Jun,Zhang, Zhaoguo,Xie, Xiaomin
supporting information
p. 1013 - 1021
(2015/03/30)

Metal-free C-N cross-coupling of electrophilic compounds and N-haloimides
When DBU is added, the cross-coupling reaction between alkyl halides (halogen = Cl, Br and I) and N-haloimides (halogen = Cl, Br) occurs, resulting in the formation of aminated products. A halogen bond activated nucleophilic substitution mechanism was proposed. The methodology represents an elegant example of applying the halogen bond activation strategy in an organic transformation.
Zhang, Luyan,Li, Yanru,Jin, Long-Yi,Liang, Fushun
p. 65600 - 65603
(2015/08/18)

Palladium-catalyzed cycloaminocarbonylation of 2-aminomethyl- and 2-alkylcarbamoylaryl tosylates with CO
The palladium-catalyzed cycloaminocarbonylation of 2-(aminomethyl)aryl tosylates with CO has been established, by which a variety of salicylaldehyde derived 2-(aminomethyl)aryl tosylates may be cyclocarbonylated in the presence of CO, to afford the corresponding substituted isoindolinones in moderate to excellent yields. Furthermore, the method is also effective for the synthesis of isoindoline-1,3-diones and 2-alkyl-1H-benzo[e]isoindol-3(2H)-ones from 2-(N-alkylcarbamoyl)aryl tosylates and 1-(aminomethyl)naphthalene-2-yl tosylates, respectively.
Liu, Bin,Wang, Yan,Liao, Benren,Zhang, Chunlei,Zhou, Xigeng
p. 5776 - 5780
(2015/09/29)

Rhodium catalyzed hydroformylation with formaldehyde and an external H 2-source
The efficiency of the syngas-free rhodium catalyzed hydroformylation of olefins with formaldehyde can be significantly improved by the addition of hydrogen gas or formic acid.
Uhlemann, Marcus,Doerfelt, Stephan,B?rner, Armin
p. 2209 - 2211
(2013/05/09)

New tetraphosphorus ligands for highly linear selective hydroformylation of allyl and vinyl derivatives
New tetraphosphorus ligands have been developed and applied in the rhodium-catalyzed regioselective hydroformylation of a variety of functionalized allyl and vinyl derivatives. Remarkably high linear selectivity was obtained by these tetraphosphorus ligands. The ligand that bears strong electron-withdrawing 2,4-difluorophenyl groups is the most effective one in affording linear aldehydes. The Rh/tetraphosphorus ligand catalyst is highly effective to produce linear aldehydes from functionalized allyl derivatives with heteroatoms or aromatic groups directly adjacent to the allyl group. For vinyl derivatives, the ligand is highly linear selective for acrylic derivatives, styrene, vinyl pyridine, and vinyl phthalimide. Linear to branch ratios of 26:1 and 10:1 were obtained for the hydroformylation of styrene and allyl cyanide, respectively. New tetraphosphorus ligands have been developed and applied in the rhodium-catalyzed regioselective hydroformylation of a variety of allyl and vinyl olefins (see scheme). Remarkably high linear selectivities were obtained by these ligands. Linear-to-branch ratios of 26:1 and 10:1 were obtained for the hydroformylation of styrene and allyl cyanide, respectively. Copyright
Cai, Chaoxian,Yu, Shichao,Cao, Bonan,Zhang, Xumu
experimental part
p. 9992 - 9998
(2012/09/07)

Rhodium(iii)-catalyzed oxidative carbonylation of benzamides with carbon monoxide
An efficient strategy for the oxidative carbonylation of aromatic amides via C-H/N-H activation to form phthalimides using an Rh(iii) catalyst has been developed. The reaction shows a preference for C-H bonds of electron-rich aromatic amides and tolerates a variety of functional groups. The Royal Society of Chemistry 2011.
Du, Ya,Hyster, Todd K.,Rovis, Tomislav
p. 12074 - 12076
(2011/12/14)

Synthesis of new cantharimide analogues derived from 3-sulfolene
New types of norcantharimide analogues were prepared by three methods: epoxidation, photooxidation, and bromination. Epoxidation of deoxynorcantharimide with m-chloroperoxybenzoic acid gave an isomeric mixture. The selective formation of the syn-isomers was attributed to dipole-dipole interactions between the peracid and imide moiety. Photooxidation of deoxynorcanthamide gave syn-and anti-hydroperoxide analogues through ene addition of singlet oxygen; the anti-hydroperoxide was the major product in this case, as a result of the steric effect of the imide ring. Bromination of deoxynorcantharimide and subsequent transformations gave a pyrrolidine and the phthalimide core structure. Georg Thieme Verlag Stuttgart.
Tan, Ayse,Koc, Birgul,Sahin, Ertan,Kishali, Nurhan H.,Kara, Yunus
p. 1079 - 1084
(2011/06/22)

N-alkylation of imides using phase transfer catalysts under solvent-free conditions
(Chemical Equation Presented) N-Alkylation of imides in the reaction of imides and alkylhalides, catalyzed by PT catalysts under solvent-free conditions, has been developed. The reaction occurs in the presence of K 2CO3, and in many cases it takes place spontaneously. In the N-benzylation reaction, it has been recognized that TBAB (tetrabutylammonium bromide) and TBATFB (tetrabutylammonium tetrafluoroborate) show highest catalytic effect. Versatility and synthetic capacity of the solvent-free alkylation has been confirmed by N-benzylation and N-ethylation of various imides. The developed procedure gives easy access to N-(ω-bromoalkyl) imides.
Jaskowska, Jolanta,Kowalski, Piotr
experimental part
p. 1371 - 1375
(2009/04/07)

KF/Al2O3-mediated N-alkylation of amines and nitrogen heterocycles and S-alkylation of thiols
KF/Al2O3 efficiently catalyzes N-alkylation of heterocyclic, primary, and secondary amines and S-alkylation of thiols with a variety of alkyl halides. The N-alkylation and S-alkylation adducts were produced in good to excellent yields and in short times. Copyright Taylor & Francis Group, LLC.
Moghaddam, Firouz Matloubi,DokhtTaimoory, Seyedeh Maryam,Ismaili, Hossein,Bardajee, Ghasem Rezanejade
p. 3599 - 3607
(2007/10/03)

Some reactions of 3-chloroisoindolium salts with nucleophiles: Access to isoindole derivatives and ellipticine analogues as potential antiviral agents
3-Chloro-2-substituted-1-oxoisoindolium hexachloroantimonate (1) reacted with water, ethanol and dimethylcyanamide to give the corresponding phthalimide derivatives 2, 3 and 4 respectively. Reaction of 1a with nitriles afforded the intermediate 2-azoniaallene salts 5 which underwent cyclisation reaction upon heating to furnish the ellipticine analogues 6. The biological activities of 6a-e against HIV-1 and HBV viruses were determined.
Hamed, Atef A.
p. 54 - 58
(2007/10/03)

Organic Reactions in Ionic liquids: N-Alkylation of Phthalimide and Several Nitrogen Heterocycles
N-Alkylation of heterocyclic compounds bearing an acidic hydrogen atom attached to nitrogen with alkyl halides is accomplished in ionic liquids ([bmim]BF4= 1-butyl-3-methylimidazolium te trafluoroborate, [bmim]PF6 = 1-butyl-3-methylimidazolium hexafluorophosphate, [buPy]BF4 = butylpyridiniurri tetrafluoroborate) in the presence of potassium hydroxide as a base. In this manner, phthalimide, indole, benzimidazole, succinimide can be successfully alkylated. The procedure is convenient, efficient, and generally affords the N-alkylated product exclusively.
Le, Zhang-Gao,Chen, Zhen-Chu,Hu, Yi,Zheng, Qin-Guo
p. 208 - 212
(2007/10/03)

Microwave-assisted N-alkylation of potassium phthalimide and potassium succinimide onto silica gel in dry media
Synthesis of N-alkyl phthalimides and N-alkyl succinimides through alkylation of potassium phthalimide and potassium succinimide in dry media catalyzed by phase-transfer catalyst under microwave irradiation will be reported. The reactions were with fairly high yield.
Hekmatshoar,Heravi,Baghernejad,Asadolah
p. 1611 - 1614
(2007/10/03)

Fluorous Mitsunobu reagents and reactions
A fully fluorous Mitsunobu reaction procedure is introduced. This employs both existing [(C6F13CH2CH2C6H 4)2PPh] and new [C8F17CH2CH2C6H 4PPh2] fluorous phosphines and a new fluorous azodicarboxylate (C6F13CH2CH2OC(O)N=NCOOCH 2CH2C6F13). A procedure involving parallel reactions with representative nucleophiles and alcohols under typical Mitsunobu conditions in THF followed by rapid solid phase extraction (spe) over fluorous silica provides clean products in excellent yields. The fluorous fraction containing the oxidized phosphine oxide and the reduced hydrazide can be readily separated and the starting reagents can be regenerated by appropriate redox reactions in high yield for reuse.
Dandapani, Sivaraman,Curran, Dennis P.
p. 3855 - 3864
(2007/10/03)

Hydrogenation of alkenes or alkynes using decaborane in methanol
Alkenes and alkynes were reduced to corresponding alkanes in methanol using decaborane (B10H14) in the presence of Pd/C as catalyst under nitrogen in high yields. (C) 2000 Elsevier Science Ltd.
Lee, Seung Hwan,Park, Yong June,Yoon, Cheol Min
p. 887 - 889
(2007/10/03)

Quantitative solid-state reactions of amines with carbonyl compounds and isothiocyanates
A series of solid-state reactions is reported of gaseous or solid amines with aldehydes to give imines, with solid anhydrides to give diamides (therefrom imides) or amidic carboxylic salts or imides, with solid imides to give diamides, with solid lactones or carbonates to give functionalized carbamic esters, with polycarbonates to give degradative aminolysis, and with solid isothiocyanates to give thioureas. Diamides give imides by solid-state thermolysis or acid catalysis. Various double, two-step, 3-cascade, and sequential reactions are reported in the solid state without melting. The yields are quantitative in 53 reported reaction examples and no workup (except for washings in four cases) is required in the 100% yield reactions. Three initially solid-state reactions but with liquid product were not quantitative. An upscaling to the kg scale shows promise of the technique for large scale applications. Supermicroscopic analyses with AFM elucidate the solid-state mechanism by virtue of far-reaching anisotropic molecular movements in three-step processes. Gas-solid aminolyses of polycarbonates are also studied with AFM. The implications to sustainable chemistry are discussed. (C) 2000 Elsevier Science Ltd.
Kaupp, Gerd,Schmeyers, Jens,Boy, Juergen
p. 6899 - 6911
(2007/10/03)

Exploratory studies probing the intermediacy of azomethine ylides in the photochemistry of N-phthaloyl derivatives of α-amino acids and β-amino alcohols
Exploratory photochemical studies with N-phthaloyl derivatives of glutamic acid, aspartic acid, serine, threonine and analogous carboxylic acids and alcohols have been conducted to determine the generality of azomethine ylide forming decarboxylation and retro-aldol fragmentation reactions. Preferences in the competition between these excited state reaction pathways have been determined by studies with phthalimides which contain both α-amino acid and β-aminoethanol groups.
Yoon, Ung Chan,Lee, Chan Woo,Oh, Sun Wha,Mariano, Patrick S.
p. 11997 - 12008
(2007/10/03)

Procedure for alkylation of imides
A process for the alkylation of imides wherein the imides are reacted with a dialkyl carbonate, in the liquid state, at a temperature of between 100° C. and 250° C. and at a pressure of between 0 and 60 atmospheres in the presence of a basic catalyst. The dialkyl carbonate reagents are not very toxic and are thermally stable and their use as alkylation agents makes it possible to produce waste products with a negligible saline content.
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(2008/06/13)

Photochemical transformations of proteinogenic and non-proteinogenic amino acids
The photochemistry of N-activated enantiomerically pure α-amino acids is described with emphasis on chemo-, regio-, stereo-, and spin selectivity. An especially valuable chromophore is the phthalimido group. The first excited singlet states are short-lived and deactivated (chemically) via homolytic CH cleavage or (physically) via electron-transfer steps. The first excited triplet states are chemically deactivated via electron-transfer reactions and subsequent deprotonation/coupling steps. A wide variety of product types were synthesized, and potential target molecules were available by tuning the reaction conditions. Also remote groups can be activated by means of electron-transfer steps, which represents an attractive new synthetic protocol for macrocyclization.
Griesbeck, Axel G.
p. 272 - 283
(2007/10/03)

Novel heterocyclic ring-expansion and/or dehydration-hydration reactions of propargylic and allenylic hydroxy γ-lactams in the presence of strong base or Lewis acid
Dehydration-hydration products were obtained in good yields by the treatment of propargylich hydroxy γ-lactams with some Lewis acids. Several propargylic and allenylic hydroxy γ-lactams were successfully converted to the corresponding ring-expanded benzazepines in various yields via a tandem decyclization-cyclization process in the presence of (TMS)2NLi, (TMS)2NNa, or n-BuLi under reflux conditions in THF.
Jeong, Ill-Yun,Lee, Woo Song,Goto, Satoru,Sano, Shigeki,Shiro, Motoo,Nagao, Yoshimitsu
p. 14437 - 14454
(2007/10/03)

Synthesis of Medium- and Large-Ring Compounds Initiated by Photochemical Decarboxylation of ω-Phthalimidoalkanoates
The synthesis of a variety of hydroxylactams from ω-phthalimidoalkanoates using a triplet-sensitized photodecarboxylation reaction initiated by intramolecular photo electron transfer is described. Ring sizes available by this method span from 4 (benzazepine-1,5-dione 7) to 26 (cyclodipeptide 26e). Ground-state template formation is proposed as the explanation for the high efficiency of this reaction and for the decrease in reactivity in the presence of organic bases instead of metal carbonates. The crucial step in this macrocyclization reaction seems to be the protonation of the intermediary ketyl radiais (Scheme 4). Spacer groups investigated were alkyl chains (C3-C11: 5c-h, 11a, 12), ether (16, 18), ester (20, 22), and amide (26a-f) linkages. Within the detection limits, no dimeric (= decarboxylative coupling) products were observed, indicating the high preference for intra-vs. intermolecular photoelectron transfer. The C,C radical combination step proceeds with low stereoselectivity (cf. products 11 and 12) in contrast to comparable singlet reactions. Except for the lactones 22, all products were stable under the photolysis conditions. Prolonged irradiation of 22 led to the formation of the spiro compounds 23, probably via an intermediary acyliminium betaine (Scheme 8). One serious limitation of the decarboxylative macrocyclization is its incompatibility with the glycine spacer (as in 27a and 27b), probably the consequence of a strong intramolecular H-bond (Scheme 10).
Griesbeck, Axel G.,Henz, Andreas,Kramer, Wolfgang,Lex, Johann,Nerowski, Frank,Oelgemoeller, Michael,Peters, Karl,Peters, Eva-Maria
p. 912 - 933
(2007/10/03)

Reaction enthalpy of nucleophilic substitution of ethyl iodide in acetonitrile and its mechanistic significance
Enthalpies of reaction for nucleophilic substitution of ethyl iodide have systematically been determined in acetonitrile. Through the concurrent analysis of empirical correlations between the reaction enthalpies and the specific interaction enthalpies for relevant anions with those between the logarithmic rates and the specific interaction enthalpies, partial desolvation accompanying activation has been deduced to be the major contributor to activation thermodynamic parameters, while the propensity of the reacting central atom in the nucleophilic anion plays a crucial role in determining reaction thermodynamic parameters. Semi-empirical molecular orbital calculations have supported these ideas. The application of the Marcus equation to the analysis of reaction characteristics in these reactions is discussed.
Kondo, Yasuhiko,Tsukamoto, Tamio,Kimura, Naoko
p. 1765 - 1769
(2007/10/03)

Photoelektronentransfer-induzierte Makrocyclisierung von N-Phthaloyl-ω-aminocarbonsaeuren
Stichworte: Aminosaeuren.Cyclisierungen.Makrocyclen.Photochemie
Griesbeck, Axel G.,Henz, Andreas,Peters, Karl,Peters, Eva-Maria,Schnering, Hans Georg von
p. 498 - 500
(2007/10/02)

Novel and efficient azomethine ylide forming photoreactions of N-(silylmethyl)phthalimides and related acid and alcohol derivatives
An investigation of the photochemistry of N-(silylmethyl)phthalimides and related α-phthaloylacetic acids and 2-phenylethanol derivatives has uncovered new excited state processes resulting in the formation of azomethine ylide intermediates. Irradiation of N-[(trimethylsilyl)methyl]phthalimide in MeCN promotes C to O silyl transfer to generate the corresponding azomethine ylide which is efficiently trapped by reaction with water to yield the N-methylphthalimide or by dipolar cycloaddition with acetone, methyl acrylate, or acrylomtrile. Cycloadditions with the latter two dipolarophiles are both regioselective and endo-stereoselective. These processes can be triplet photosensitized by use of acetophenone. The related N-[(trimethylsilyl)methyl]-1,8-naphthalimide reacts in a similar manner upon irradiation in MeCN solutions containing the dipolarophiles methyl acrylate and acrylonitrile to produce cycloadducts which undergo spontaneous elimination of TMSOH, yielding α,β-unsaturated ester or nitrile products. The ylide formed by irradiation of the (silylmethyl)phthalimide is trapped in a stereospecific (retention) manner by the dipolarophiles trans-hex-4-en-3-one, dimethyl maleate, and dimethyl fumarate. The effect of aryl ring substitution on the regiochemical course of the photoinduced C to O silyl migration process was probed by use of the 4-methoxy-and 4-carbomethoxyl-N-(silylmethyl)phthalimides. Irradiation of the former substance in an MeCN solution containing acrylonitrile gives rise to a single adduct whose structure suggests that silyl migration to oxygen of the carbonyl meta to the OMe substituent is highly favored. In contrast, the 4-carbomethoxyphthalimide is converted under these conditions to a mixture of regioisomeric adducts. Thus, silyl migration in the excited state of this substance is nonselective. In accord with hints found in earlier observations made by Kanaoka (Chem. Pharm. Bull. 1982, 30, 1263), N-phthalimide derivatives of the α-amino acids glycine, alanine, and phenylalanine undergo similar ylide forming photoreactions upon irradiation in MeCN solutions. The azomethine ylides produced by photodecarboxylation of these substances are efficiently trapped by dipolarophiles, and the overall photoreactions starting with the alanine and phenylalanine derivatives are highly stereoselective. Finally, the N-phthalimide derivative of 2-amino-1-phenylethanol also is transformed to a related ylide upon irradiation in MeCN. The nature, regiochemical and stereochemical course, and mechanistic interpretation of these new azomethine ylide forming photoreactions are discussed in this publication.
Yoon, Ung Chan,Kim, Dong Uk,Lee, Chan Woo,Choi, Young Sun,Lee, Yean-Jang,Ammon, Herman L.,Mariano, Patrick S.
p. 2698 - 2710
(2007/10/02)

Compounds having antihypertensive and anti-ischemic properties
This invention relates to adenosine derivatives and analogs which possess adenosine agonist activity and are useful as anti-hypertensive and anti-ischemic agents, to pharmaceutical compositions including such compounds, and to their use in treating hypertension and myocardial ischemia, and to methods and intermediates used in the preparation of such compounds.
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(2008/06/13)

Nucleophilic Reactivity and Solvation of Succinimide and Phthalimide Anions in Acetonitrile-Methanol Mixtures
Nucleophilic reactivity and solvation patterns for succinimidide ions have been characterized through three procedures, kinetic and enthalpy of solution measurements in acetonitrile-methanol mixtures, and enthalpy of reaction measurements in acetonitrile.Quantitative analysis indicates that activation enthalpy vs. activation entropy correlation is more sensitive and versatile than activation enthalpy vs. reaction correlation as the method for detecting the effects of various molecular interactions on rates of reaction.Any essential difference in nucleophilic reactivities and in solvation patterns was not observed between imidide and carboxylate ions, but a significant difference is found on the pKa values in the aqueous phase and on the enthalpy of reaction with ethyl iodide in acetonitrile.
Kondo, Yasuhiko,Kondo, Kunio,Kusabayashi, Shigekazu
p. 1141 - 1145
(2007/10/02)

Studies on the Chemistry of Isoindoles and Isoindolenines, XXXV. 1-Alkoxy-2-alkyl-2H-isoindoles - o-Quinonoid Hetarenes with Unsymmetric Structure
3-Alkoxy-2-methyl-1H-isoindolium salts have been prepared either via regioselective O-alkylation of the corresponding 2-alkyl-isoindoline-1-ones or via regioselective N-alkylation of 3-alkoxy-1H-isoindoles with trialkyloxonium tetrafluoroborates or with alkyl trifluoromethanesulfonates.Deprotonation of these stable precursors leads to the generation of reactive 1-alkoxy-2-alkyl-2H-isoindoles in solution.Reactions with CC-dienophiles (N-substituted maleic imides) give rise to the formation of 1:2-adducts.The two step reaction comprises Michael-addition and Diels-Alder-addition; the isolation of an initially formed 1:1-adduct is possible in the case of steric hindrance.Constitution and configuration of a representative 1:2-adduct has been established by X-ray crystal structure determination. - Keywords: 1-Alkoxy-2-alkyl-2H-isoindoles, Generation and Characterization, Addition and Cycloaddition Reactions with CC-Dienophiles
Kreher, Richard P.,Hennige, Hans,Jelitto, Frank,Preut, Johannes
p. 1132 - 1148
(2007/10/02)

PHOTOREDUCTION DE LA BENZOPHENONE PAR DES PHTALIMIDINES ET DES DIHYDRO ISOQUINOLONES. ETUDE CHIMIQUE ET PAR RMN PNIC
Benzophenone is photoreduced by phtalimidines and dihydro isoquinolones.The hydrogen atom α to the nitrogen atom is abstracted and radical coupling leads to adducts.CIDNP studies of these adducts show inversion of polarisation for the adduct on the N-alkyl chain when the nitrogen is bound to a benzylic methylene.This inversion is explained by considering that the radical on the N-alkyl chain derives from the radical on the ring.
Gramain, J. C.,Simonet, N.,Vermeersch, G.,Febvay-Garot, N.,Caplain, S.,Lablache-Combier, A.
p. 539 - 550
(2007/10/02)

Photodecarboxylation of N-Phthaloyl-α-amino Acids
N-Phthaloylglycine (1a) was irradiated with a high pressure mercury lamp to give N-methylphthalimide (2a) in an excellent yield.N-Phthaloyl derivatives 1b-k of other α-amino acids also afforded the decarboxylated products 2b-k.In the cases of N-phthaloylserine (11) and di-phthloylcystine (1m), N-vinylphthalimide (3) was isolated as a major product.On the other hand, N-phthaloylmethionine (11a) and methyl N-phthaloylmethionate (11b) were treated in the same manner to give the aza-thiacyclo-heptanol derivatives 12a-b having a new ring system.Solvent effects and possible pathways of these reactions were examined.Keywords- N-phthaloyl-α-amino acid; photolysis; decarboxylation; cyclization; efficiency; solvent effect; υ-hydrogen abstraction
Sato, Yasuhiko,Nakai, Hideo,Mizoguchi, Tomishige,Kawanishi, Masazumi,Hatanaka, Yasumaru,Kanaoka, Yuichi
p. 1263 - 1270
(2007/10/02)

Orthoamides, XXXVIII. - Contributions to the Chemistry of Orthocarbonic Acid Esters and α,α,α-Trialkoxyacetonitriles
The reactivity of the orthocarbonates 4 and the nitriles 1 has been investigated.Carboxylic acids are esterified by 4b. Orthocarbonates 4c-f and 9b are prepared by transesterification of 4b.Mixed substituted orthocarbonates 8c-f are obtained from the nitriles 1a,b.The nitriles 2a and 3a react with alkali alcoholate in alcohol to yield the orthocarbamic acid esters 13a,b. Spirocyclic orthocarbonates 17a-d are prepared from 4b and 1,2 or 1,3-dioles, respectively. The reaction of phenol with 1b affords the mixed substituted orthocarbonate 18a. Catechol is converted by 1a into the orthocarbonate 20a.Reactions of 4b with amines and ami ne derivatives are studied. In the course of these investigations guanidines 21, imidocarbonic acid esters 22a-c, 30, carbamic acid esters 25, ureas 26, the isourea derivative 29, as well as the 1,3,4-oxadiazole 31 are prepared. The mechanism of these reactions is discussed. Imidocarbonic acid esters 22d-f, 38, N-cyanocarbamates 39, and isoureas 37 can be prepared from 1b and amines or amine derivatives. 2a as well as 13b react with cyanamide to give the N-cyanoisourea 40. Ureas 26 are formed in the reaction of 1a,b with secondary amines at elevated temperatures.The guanidinium cyanide 41a can be obtained by reaction of pyrrolidine with 1b in ether, whereas under similiar conditions from 1a and pyrrolidine the amidine 42 is produced. o-Aminophenol, o-phenylenediamine and anthranilic acid are cyclized by 4b or 1b to afford the heterocyclic compounds 43-45. α- and β-amino acids are transformed by 4b or 1b into the N-(ethoxycarbonyl)amino acid esters 46 and 47, respectively.
Kantlehner, Willi,Maier, Thomas,Loeffler, Wolfgang,Kapassakalidis, Joanis J.
p. 507 - 529
(2007/10/02)

Ortho-effects in 1-(2-Aminomethylaryl)-1-buten-3-ones and Their Hydrogenation Products, II: 2-(Aminomethyl)phenylmethylenacetones and Their Hydrogenation Products, I
The preparations of the compounds 3-13 are described.
Mayer, Klaus K.,Poettinger, Theodor,Wiegrebe, Wolfgang
p. 669 - 674
(2007/10/02)

Heterocycles in Organic Synthesis. Part 42. Preparation of Azides, Phthalimides, and Sulphonamides from Primary Amines
N-Alkyl and N-benzyl substituents are displaced from 2,4,6-triphenylpyridinium cations by nucleophilic azide, phthalimide, succinimide, and sulphonamide anions.This enables the conversion of primary alkyl- and benzylamines into azides, and primary (with potential for inversion or labelling) and secondary amines.
Katritzky, Alan R.,Liso, Gaietano,Lunt, Edward,Patel, Ranjan C.,Thind, Sukhpal S.,Zia, Abid
p. 849 - 851
(2007/10/02)

EFFETS DE CRYPTANDS ET ACTIVATION DE BASES-Va ACTION DES HYDRURES ALCALINS SUR LES ACIDES FAIBLES-II. ALKYLATION DES ANIONS OBTENUS
Phenoxides, alkoxides and potassium amidates generated by KH in THF or benzene at room temperature are easily alkylated in the presence of catalytic quantities of crytand, without affecting addition-elimination ratios.Thus, Williamson and Gabriel syntheses, as well as the alkylation of secondary amines, occur readily in mild conditions.
Pasquini, M. A.,Goaller, R. Le,Pierre, J.L.
p. 1223 - 1226
(2007/10/02)