Sulfur-substituted quinolizidines and pyrido [1, 2-a] azepines (7) can be prepared by ring- closing metathesis (RCM) of 4-(phenylthio)-1, 2, 5, 6-tetrahydropyridin-2-ones (6) bearing terminal alkenyl groups at both N-1 and C-6 positions, which are obtained from 3- (phenylthio)-3-sulfolene (1) in four steps. Some synthetic transformations of 2-(phenylthio)-1, 6, 9, 9a-tetrahydroquinolizin-4-one (7a) and 2-(phenylthio)-1, 6, 9, 10, 10a- ...
