A novel synthetic approach to benzo[h]chromones via sequential intramolecular alkynoyl transfer followed by 6-endo ring closure
作者:Katsuji Sakamoto、Erina Honda、Noboru Ono、Hidemitsu Uno
DOI:10.1016/s0040-4039(00)00037-x
日期:2000.3
An intramolecular acyl transfer reaction took place on treatment of 1-methoxymethoxy-3-(2-alkynoyloxy)methyl-2-iodonaphthalenes with n-BuLi at -78 degrees C to give 1-methoxymethoxy-2-alkynoyl-3-hydroxymethylnaphthalenes in high yields. After protection of the hydroxymethyl group as benzoates, formation of a phi-pyrone ring was easily achieved by deprotection of the MOM group followed by spontaneous 6-endo-digonal ring closure under mild acidic conditions. (C) 2000 Elsevier Science Ltd. All rights reserved.