320344-83-0Relevant academic research and scientific papers
The hydroboration of propargyl bromide. Simple one-pot three-component routes to (Z)-1-bromoalk-1-en-4-ols and to anti-homoallylic alcohols
Lombardo,Morganti,Trombini
, p. 8767 - 8773 (2007/10/03)
The hydroboration of propargyl bromide with dialkylboranes takes place regioselectively to give 3-bromoprop-1-en-1-yl dialkylboranes 13 which, upon quaternization with bromide ion, undergo a series of transformations into a number of allylic boron species. By a suitable choice of the experimental conditions it is possible to trap the reaction intermediates with aldehydes and to steer the process toward either the synthesis of (Z)-1-bromoalk-1-en-4-ols 6 or anti-homoallylic alcohols 8. Two one-pot three-component processes were developed based on a sequence of four reactions; preparation of dialkylborane and hydroboration of propargyl bromide are the first steps. Then, quaternization with TEBABr may be carried out either in the presence of the aldehyde when (Z)-1-bromoalk-1-en-4-ols 6 are requested, or in the absence of the aldehyde in order to allow the formation of γ-substituted allyl borane 18 which, successively, adds to the aldehyde affording antihomoallylic alcohols 8.
