Pyrrolidinone-and piperidinone-derived enol triflates 2 were prepared in high yield (60-97%) from the corresponding lactams 1 using KHMDS and N-(5-chloro-2-pyridyl) triflimide. A structure-stability study on the less stable pyrrolidinone-derived triflates revealed that an N- tosyl group is essential, and an α-ethoxy substituent enhances thermal stability. Substituents at the 3-and 4-position are tolerated. Substitution of the triflate moiety by a wide variety of ...
