Expansive Rearrangement of N-Vinylthiazolidines to 2,3,4,7-Tetrahydro-1,4-thiazepines and their Transformation in 3-Thia-6-azabicyclo[3.2.1]oct-6-enes - Calvo, Luis; González-Ortega, Alfonso; Pérez, Mónica; Sañudo, María Carmen (Synlett, 2005)