Functionalized Alkenylzinc Reagents Bearing Carbonyl Groups: Preparation by Direct Metal Insertion and Reaction with Electrophiles
作者:Christoph Sämann、Matthias A. Schade、Shigeyuki Yamada、Paul Knochel
DOI:10.1002/anie.201302058
日期:2013.9.2
cyclic and acyclic alkenylzinc reagents bearing functional groups such as aldehyde, keto, and ester groups were readily prepared by either direct zinc insertion in the presence of LiCl or by magnesiuminsertion in the presence of LiCl and ZnCl2. Subsequent functionalization reactions, such as Negishi cross‐couplings, acylations, and allylations, furnished polyfunctional compounds in excellent yields
Selective Mono- and 1,2-Difunctionalisation of Cyclopentene Derivatives via Mg and Cu Intermediates
作者:Christina Despotopoulou、Richard C. Bauer、Arkady Krasovskiy、Peter Mayer、Jeffrey M. Stryker、Paul Knochel
DOI:10.1002/chem.200701431
日期:2008.3.7
A single Br/Mg exchange of 1,2-dibromocyclopentene with iPrMgCl LiCl provides the corresponding beta-bromocyclopentenylmagnesium reagent, which can then be reacted with various electrophiles (yields: 65-82 %). In the presence of a secondary alkylmagnesium halide and Li2CuCl4 (2 mol %), these 2-bromoalkenylmagnesium compounds undergo bromine substitution and can then further react with electrophiles