Diastereoselectivity in the [2,3]-sigmatropic rearrangement of substituted allylic N,N-dialkylamidosulfoxylates. X-ray molecular structure of [(1′) S*, (S)S*]-(2′E)-4-[[3′-(4″-bromophenyl)-1′-methyl- 2′-propenyl]sulfinyl]-morpholine

Article abstract of DOI:10.1016/S0040-4020(01)82318-8

By the reaction with three N,N-dialkylamidosulfenyl chlorides 2 bearing representative sizes for the R groups on the nitrogen atom, several substituted secondary E or Z allylic alcohols (1a-h) have been converted into the corresponding pairs of diastereoisomeric allylic sulfinamides (3+-3′a-v), whose ratios have been determined by ¹H NMR spectroscopy. Five cases of entirely diastereoselective [2,3]-sigmatropic rearrangement have been observed. The stereochemistry of one pure diastereoisomer 3′m has been determined by single crystal X-Ray analysis. When treated with 4-morpholinesulfenyl chloride, cyclohex-2-en-1-ol is stereoselectively converted to one diastereoisomer of the sulfinamide 5b which, by unambiguous procedures, led to the sane p.tolylsulfoxide 5a already obtained by treatment of cyclohex-2-en-1-ol with toluene-p-sulfenyl chloride.