Carbenoid rearrangement of gem-dihalogenospiropentanes
摘要:
A skeletal rearrangement of dihalogenospiropentanes in the presence of alkyllithium reagents has been systematically studied using a number of gem-dibromospiropentanes. The scope and limitations of this carbenoid rearrangement are outlined and its mechanism is discussed. (c) 2006 Elsevier Ltd. All rights reserved.
A new reaction of 1-bromoalk-1-ynes; synthesis of 3-alkylalk-1-ynes from terminal acetylenes
作者:Augustus J. Quillinan、Ejaz A. Khan、Feodor Scheinmann
DOI:10.1039/c39740001030
日期:——
The reaction of 1-bromoalk-1-ynes with two equivalents of butyl-lithium in hexane gives 3-butylalk-1-ynes; the reactive intermediate is a dilithioalkyne which can also be directly prepared fromterminalacetylenes, and selective reaction with alkyl halides in hexane occurs at the propargylic site to provide a general synthesis of 3-alkylalk-1-ynes.
gem-Bromochlorospiropentane reactivity toward methyllithium: an unusual carbenoid rearrangement
作者:Kseniya N. Sedenkova、Elena B. Averina、Yuri K. Grishin、Tamara S. Kuznetzova、Nikolai S. Zefirov
DOI:10.1016/j.tet.2010.07.054
日期:2010.10
A skeletal carbenoid rearrangement of the gem-bromochlorospiropentanes in the presence of methyllithium has been studied. The synthetic and mechanistic aspects of this rearrangement as well as the influence of the halogen atom nature on the reaction pathway are discussed. (C) 2010 Elsevier Ltd. All rights reserved.