Isothiourea-Catalyzed Enantioselective Functionalization of 2-Pyrrolyl Acetic Acid: Two-Step Synthesis of Stereodefined Dihydroindolizinones
作者:Shuyue Zhang、James E. Taylor、Alexandra M. Z. Slawin、Andrew D. Smith
DOI:10.1021/acs.orglett.8b02423
日期:2018.9.7
Catalytic enantioselective functionalization of 2-pyrrolyl acetic acid with trichloromethyl enones using isothiourea catalysis is reported, leading to a range of stereodefined diesters and diamides after nucleophilic ring opening with either methanol or benzylamine (30 examples, up to >95:5 dr and >99:1 er). Subsequent intramolecular Friedel–Craftsreaction allows access to dihydroindolizinones in high yields
Organocatalytic Michael addition–lactonisation of carboxylic acids using α,β-unsaturated trichloromethyl ketones as α,β-unsaturated ester equivalents
作者:Louis C. Morrill、Daniel G. Stark、James E. Taylor、Siobhan R. Smith、James A. Squires、Agathe C. A. D'Hollander、Carmen Simal、Peter Shapland、Timothy J. C. O'Riordan、Andrew D. Smith
DOI:10.1039/c4ob01788a
日期:——
Isothiourea HBTM-2.1 catalyses the Michael addition–lactonisation of 2-aryl and 2-alkenylacetic acids and α,β-unsaturated trichloromethyl ketones. Ring-opening of the resulting dihydropyranones and subsequent alcoholysis of the CCl3 ketone with an excess of methanol gives a range of diesters in high diastereo- and enantioselectivity (up to 95 : 5 dr and >99% ee). Sequential addition of two different
The invention concerns a method for preparing &agr;-halogenated ketones from secondary &agr;-halogenated alcohols. More particularly, the invention concerns the preparation of &agr;-trihalogenated ketones from secondary &agr;-trihalogenated alcohols. The method for preparing said &agr;-halogenated ketone is characterized in that it consists in oxidizing in liquid phase, a secondary &agr;-halogenated alcohol, using molecular oxygen or a gas containing same, in the presence of a catalyst based on a metal M
1
selected among metals of group 1b and 8 of the periodic system of elements and optionally an activating element.
PROCEDE DE PREPARATION DE CETONES ALPHA-HALOGENEES
申请人:RHODIA CHIMIE
公开号:EP1250303A1
公开(公告)日:2002-10-23
[EN] METHOD FOR PREPARING ALPHA-HALOGENATED KETONES<br/>[FR] PROCEDE DE PREPARATION DE CETONES ALPHA-HALOGENEES
申请人:RHODIA CHIMIE SA
公开号:WO2001055067A1
公开(公告)日:2001-08-02
La présente invention a pour objet un procédé de préparation de cétones α-halogènées à partir d'alcools secondaires α-halogénés. L'invention vise plus particulièrement la préparation de cétones α-trihalogénées à partir d'alcools secondaires α-trihalogénés. Le procédé de préparation d'une cétone α-halogénée selon l'invention est caractérisé par le fait qu'il consiste à oxyder en phase liquide, un alcool secondaire α-halogéné, à l'aide d'oxygène moléculaire ou un gaz en contenant, en présence d'un catalyseur à base d'un métal M1 choisi parmi les métaux du groupe 1b et 8 de la classification périodique des éléments et éventuellement d'un activateur.