Electrophilic <i>ipso</i>-Cyclization of <i>N</i>-(<i>p</i>-Methoxyaryl)propiolamides Involving an Electrophile-Exchange Process
作者:Bo-Xiao Tang、Qin Yin、Ri-Yuan Tang、Jin-Heng Li
DOI:10.1021/jo8018297
日期:2008.11.21
A novel electrophilic ipso-cyclization involving an electrophile-exchange process has been developed. In the presence of CuX (X = I, Br, SCN) and electrophilic fluoride reagents, a variety of N-(p-methoxyaryl)propiolamides and 4-methoxyphenyl 3-phenylpropiolate were cyclized to selectively afford the corresponding spiro[4.5]decenones in moderate to good yields. It is noteworthy that two azaquaternary tricyclic products were synthesized through a two-step pathway involving an electrophilic ipso-cyclization and then an intramolecular Heck reaction.