STEREOCHEMICAL COURSE OF THE -SIGMATROPIC REARRANGEMENT OF SUBSTITUTED PROPARGYL N,N-DIALKYLAMIDOSULFOXYLATES. X-RAY MOLECULAR STRUCTURE OF *,(S)R*>-4--MORPHOLINE.

Article abstract of DOI:10.1016/S0040-4020(01)86400-0

By the reaction with three N,N-dialkylamidosulfenyl chlorides 2 bearing representative sizes for the R group on the nitrogen atom, several substituted secondary propargylic alcohols (1a-f) have been converted into the corresponding pairs of diastereoisomeric allenic sulfinamides 3a-n and 3'a-j, l, m.Their ratios have been determined by 1H NMR spectroscopy and were found to depend essentially on the sizes of both the R¹ and R groups of the starting materials.The stereochemistry of one pure diastereoisomer 3m has been determined by a single crystal X-ray analysis.When treated with p-toluenesulfenyl chloride, the alcohol 1f led to a major α-allenic sulfoxide 5 which was found to be identical to that prepared by unambiguous procedures from the major α-allenic sulfinamide 3m.