A Direct Synthesis of Allenes by a Traceless Petasis Reaction
作者:Devon A. Mundal、Kelly E. Lutz、Regan J. Thomson
DOI:10.1021/ja301489n
日期:2012.4.4
A one-pot synthesis of allenes by the 2-nitrobenzenesulfonylhydrazide-mediated coupling of hydroxyaldehydes or ketones with alkynyl trifluoroborate salts is reported. This mild process involves in situ formation of a sulfonylhydrazone that reacts with alkynyl trifluoroborates to generate a transient propargylic hydrazide species. Decomposition of this unstable hydrazide via an intermediate monoalkyldiazine
using n-Bu4NBr afforded 2-cyano-2-siloxyvinylallenes via a tandem process that involves a nucleophilic attack of a cyanide ion and a Brookrearrangement induced conjugate vinylic 1,4-elimination. Use of a chiral cyanide ion source, derived from KCN and quaternary ammonium bromide derived from cinchona alkaloids, provided nonracemic allene derivatives. Based on this result and the reaction using a chiral
Reduction d'acetals γ-bromo α-acetyleniques par les sels chromeux : Acces aux acetals et aldehydes α-alleniques.
作者:B. Ledoussal、A. Gorgues、A. Le Coq
DOI:10.1016/s0040-4039(00)98463-6
日期:1985.1
Réduction par les ions chromeux de derives bromopropargyliques en composés alléniques. application à la synthese de la phéromone de la bruche du haricot sec11Communications prĺiminairs: A. Gorgues et A. le Coq, Soc. Chim. Fr. (section Ouest), Angers, 4 Décembre 1980 et A. Gorgues, A. le Coq et B. le Doussal, Poster au colloque de Chimie francias-allemand Rennes-Erlangen, Rennes, 15 October 1981.
作者:B. le Doussal、A. le Coq、A. Gorgues、A. Meyer
DOI:10.1016/s0040-4020(01)91936-2
日期:——
OEHLSCHLAGER, A. C.;CZYZEWSKA, E., TETRAHEDRON LETT., 1983, 24, N 50, 5587-5590