Chemistry Letters, Vol.31, No.2, 134-135, 2002
A novel reaction promoted by hydrogen polyiodides (HI2n+1): Cyclization of 1-(1H-3-indolyl)-4-(methylthio)-2-(p-tolylsulfonyl)-1,3-butadienes accompanied with 1,2-sulfonyl migration
Reaction of 1-(1H-3-indolyl)-4-(methylthio)-2-(p-tolylsulfonyl)-1,3-butadienes (1) with iodine was accompanied with an unusual 1,2-migration of the sulfonyl group to give an abnormal cyclization product (3). This 1,2-migration reaction was brought about by the action of hydrogen polyiodides that are produced from excess 12 and EtSH. It is noteworthy that the reaction of I with HI resulted in formation of a normal product (2).