Reversal of expected stereochemical outcome in the oppolzer reaction of a cyclic N-enoylsultam: Enantioselective synthesis and absolute configuration of antispermatogenic hexahydroindeno[1,2-c]pyridines

Article abstract of DOI:10.1016/S0040-4039(97)00714-4

p-Tolylmagnesium bromide added with high enantioselectivity to a cyclic enoylsultam (4), but the diastereofacial selectivity (determined by X-ray crystallography of the product) was opposite that reported for acyclic enoylsultams. The reaction was used in an enantioselective synthesis of antispermatogenic hexahydroindenopyridines and allowed the absolute configuration of the active enantiomer (1) to be determined.