Electrophilic olefin heterocyclization in organic synthesis. Stereoselective synthesis of 4,5-disubstituted .gamma.-lactams by iodine-induced lactam formation of .gamma.,.delta.-unsaturated thioimidates
Electrophilic olefin heterocyclization in organic synthesis. Stereoselective synthesis of 4,5-disubstituted .gamma.-lactams by iodine-induced lactam formation of .gamma.,.delta.-unsaturated thioimidates
A novel and mild alpha-iodination of carboxamides was developed. Unsaturated amides could be converted to the alpha-iodoamides in moderate to good yields by treatment with I2 in the presence of s-collidine.
Diastereoselective α-iodination reaction of 4-alkenylamide having a β-chiral center
alpha-Iodination reaction of 4-alkenylamide with a beta-chiral center proceeds with high diastereoselectivity to give syn alpha-iodoalkenamide through the formation of cyclic ketene N,O-acetal and subsequent alpha-iodination from the opposite side of a beta-substituent. (C) 1997 Elsevier Science Ltd.
TAKAHATA, HIROKI;TAKAMATSU, TAMOTSU;YAMAZAKI, TAKAO, J. ORG. CHEM., 54,(1989) N0, C. 4812-4822
Electrophilic olefin heterocyclization in organic synthesis. Stereoselective synthesis of 4,5-disubstituted .gamma.-lactams by iodine-induced lactam formation of .gamma.,.delta.-unsaturated thioimidates