An electrophilic thiocyanation/ipso-cyclization leading to spirocyclohexadienones

A Lewis acid-catalyzed cyclization of N-(p-methoxyphenyl)-3-phenylpropionamide with N-thiocyanosuccinimide has been accomplished under mild conditions. Thus, a series of thiocyanato-containing spirocyclohexadienones was obtained in moderate to excellent yields with a good functional group tolerance and a wide range of substrates. It provides an alternative approach for the synthesis of functionalized spirocyclohexadienones.