Improved synthesis of phenylethylamine derivatives by Negishi cross-coupling reactions
作者:Craig M.L. Goddard、Ahmad Reza Massah、Richard F.W. Jackson
DOI:10.1016/j.tet.2010.09.074
日期:2010.11
Trifluoroacetamido-protected beta-aminoalkylzinc iodides undergo Negishi cross-coupling reaction with aryl iodides in moderate to excellent yields (42-84%) based on the corresponding trifluoroacetamido-protected beta-aminoalkyl iodides employing a catalyst prepared in situ from Pd-2(dba)(3) and SPhos (1 2 M ratio) In general meta- and para-substituted aryl iodides give good results using relatively low levels of catalyst [0 25 mol % Pd-2(dba)(3)] but more hindered ortho-substituted examples require higher catalyst loadings The preparation of trifluoroacetamido-protected beta-aminoalkyl iodides is straightforward and the intermediates are significantly more stable than the corresponding Hoc-protected derivatives (C) 2010 Elsevier Ltd All rights reserved