A highly regioselective reduction of propargylic acetates has been attained by using SmI2 and catalytic Pd(0) in the presence of 2,4-dimethyl-3-pentanol affording various types of allenes in high yields.
Alkynes may be easily alkylated by sequential treatment with n-BuLi followed by an alkyl halide in THF. Primary iodides give excellent yields (75-99%) as do bromides in the presence of catalytic amounts of Bu4NI or NaI; in the absence of an iodide source, bromides react poorly. This method offers advantages over existing methods which use HMPA or NH3 as co-solvents. (C) 2001 Elsevier Science Ltd. All rights reserved.
BACK, THOMAS G.;KRISHNA, M. VIJAYA;MURALIDHARAN, K. RAMAN, J. ORG. CHEM., 54,(1989) N7, C. 4146-4153
作者:BACK, THOMAS G.、KRISHNA, M. VIJAYA、MURALIDHARAN, K. RAMAN