It′s a cinch! The title reaction with azomethineimines 1 uses an operationally simple procedure, based on the combination of the bromide salt of cinchona alkaloids (3) and KOH. The procedure is reliable and general. Trifluoromethyl‐substituted amines can be accessed by a two‐step deprotection of the product (S)‐2.
[EN] PROCESS FOR THE PREPARATION OF GAMMA AMINO ACIDS AND INTERMEDIATES USED IN SAID PROCESS<br/>[FR] PROCÉDÉ DE PRÉPARATION DE ACIDES AMINÉS GAMMA ET INTERMÉDIAIRES UTILISÉS DANS CE PROCÉDÉ
申请人:ROYAL COLLEGE OF SURGEONS IE
公开号:WO2013076225A1
公开(公告)日:2013-05-30
The invention relates to the preparation of gamma amino acids of formula (I) and pharmaceutically acceptable salts, solvates and prodrugs thereof, and to intermediates used for their preparation. (formula I) wherein R1 is selected from an alkyl group, an alkenyl group, an alkynyl group and a cycloalkyl group, each of which may be optionally substituted and * denotes a chiral centre. In particular, the present invention provides an efficient synthesis of (S)-pregabalin which is suitable for carrying out on an industrial scale.
Catalytic Asymmetric Conjugate Addition of Nitroalkanes to 4-Nitro-5-styrylisoxazoles
作者:Andrea Baschieri、Luca Bernardi、Alfredo Ricci、Surisetti Suresh、Mauroâ F.â A. Adamo
DOI:10.1002/anie.200905018
日期:2009.11.23
Nitro versus nitro: 4‐Nitro‐5‐styrylisoxazoles were used as masked α,β‐unsaturated carboxylic acids in the titled catalyticasymmetric transformation. The 4‐nitroisoxazole core acts as an activator of the conjugated alkene and a latent carboxylate functionality. The reaction proceeded with 5 mol % of a readily prepared phase‐transfer catalyst at room temperature with remarkable diastereo‐ and enantioselectivity
Catalytic enantioselective addition of isocyanoacetate to 3-methyl-4-nitro-5-styrylisoxazoles under phase transfer catalysis conditions
作者:Paolo Disetti、Maria Moccia、Diana Salazar Illera、Surisetti Suresh、Mauro F. A. Adamo
DOI:10.1039/c5ob01880c
日期:——
The reaction between 3-methyl-4-nitro-5-styrylisoxazoles and ethyl isocyanoacetate proceeded under phasetransfercatalysis to give enantioenriched monoadducts in high enantiomeric excess (up to 99% ee). The resulting adducts were subsequently cyclised to give 2,3-dihydropyrroles and substituted pyrrolidines in identical high ees and as a single diastereoisomer.
Organocatalyzed Enantioselective
Synthesis of Nitroalkanes Bearing All-Carbon Quaternary
Stereogenic Centers through Conjugate Addition of Acetone Cyanohydrin
作者:Mariafrancesca Fochi、Alfredo Ricci、Luca Bernardi、Francesco Fini
DOI:10.1055/s-2008-1078496
日期:——
The first organocatalyzed phase-transfer enantioselective conjugateaddition of cyanide ion derived from acetone cyanohydrin to β,β'-disubstituted nitroolefins is reported. The reaction leads to the efficient formation of nitroalkanes bearing an all-carbonquaternarystereogeniccenter in up to 72% ee.
报道了第一个有机催化相转移对映选择性共轭加成从丙酮氰醇衍生的氰化物离子到 β,β'-二取代硝基烯烃。该反应导致有效形成具有高达 72% ee 的全碳四元立体中心的硝基烷烃。