Investigation of the stereochemistry of the [3.3]-sigmatropic rearrangement of the sp-isomer of 2-allylthio-5-acetyl-6-methyl-4-(2-nitrophenyl)-3-cyano-1,4-dihydropyridine

The reaction of the syn-periplanar conformer (the sp-isomer) of morpholinium 5-acetyl-6-methyl-4-(2-nitrophenyl)-3-cyano-1,4-dihydropyridine-2-thiolate with allyl bromide proceeds regio- and stereoselectively with the formation of the sp-isomer of the substituted 2-allylthio-1,4-dihydropyridine. The 3.3]-sigmatropic rearrangement of the last leads to the sp-isomer of 3,4-trans-3-allyl-5-acetyl-6-methyl-4-(2-nitrophenyl)-3-cyano-1,2,3,4-tetrahydropyridine-2(1H)-thione.Deceased.A. N. Nesmeyanov Institute of Hetero-organic Compounds, Russian Academy of Sciences (RAN), Moscow 117813. N. D. Zelinskii Institute of Organic Chemistry, RAN, Moscow 117913. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 643–652, May, 1997.