Direct synthesis of methyl 2-diazo-4-aryl-3-butenoates and their application to the enantioselective synthesis of 4-aryl-4-(1-naphthyl)-2-butenoates
摘要:
An improved one-flask synthesis of various methyl 2-diazo-4-aryl and 4-heteroaryl-3-butenoates, precursors to donor/ acceptor Substituted carbenoids, is described. Their Rh-2(S-DOSP)(4) catalyzed reaction with 1-acetoxy-3,4-diliydronaphthalene, via a combined C-H activation/Cope rearrangement pathway followed by elimination of acetic acid affords a highly enantioselective (98-99% ee) entry to methyl 4-aryl- and 4-heteroaryl-4-(1-naphthyl)-2-butenoates. (c) 2006 Elsevier Ltd. All rights reserved.