Reactions of 3-alkyl- and 3,3-dialkyl-1-bromoallenes with organocuprates: Effects of the nature of the cuprate reagent on the regio- and stereoselectivity
作者:Anna Maria Caporusso、Carmela Polizzi、Luciano Lardicci
DOI:10.1016/s0040-4039(00)96867-9
日期:1987.1
Organocuprates induce 1,3- and direct substitution in 3-alkyl- and 3,3-dialkyl-1-bromo-1,2-dienes leading respectively to either terminal acetylenes or allenic hydrocarbons. The nature of the cuprate exerts a prominent role in determining both the regio- and the stereochemistry of these reactions.
Organometalliques portant une fonction eliminable en β
作者:Jean Villieras、Cathy Bacquet、Jean F. Normant
DOI:10.1016/s0022-328x(00)89303-1
日期:1975.9
warming, either by α-elimination of ClLi or β-elimination of ROLi. β-Elimination is generally observed and leads to the formation of a dichloroalkene which reacts with excess of butyllithium (or lithiumdialkylamide) to give the corresponding mono-substituted alkyne (or chloroalkyne) with good yields. α-Elimination is followed by the migration of a group from the alcoholic carbon to the carbenoid center;
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.