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Ethynedithiol-based polyeneoligosulfides have been synthesized in 96% yield by the reaction of sodium acetylides (HCBCNa, NaCBCSNa) and elemental sulfur through the NaÀ ÀC sp bond in liquid ammonia with the following spontaneous polymerization of ethynedithiols (HSCBCSH) formed by the hydrolysis. The polyeneoligosulfides synthesized are brown powders (up to 77% sulfur content, mp 128-1848C), partially soluble in organic solvents.

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Heterocyclization of ketoximes with propyne or allene in superbase systems MOR/DMSO (M = K, Cs; R = H, t-Bu), which leads to 2-alkyl(aryl, hetaryl)-5-methyl-and 2,3-dialkyl-5-methylpyrroles or 2-methyl-4,5,6,7-tetrahydroindole in yields of up to 63%, has been accomplished for the first time. The reaction is mostly regioselective affording mainly or exclusively 2,5-di-and 2,3,5-trisubstituted pyrroles. The minor isomers in most cases are the corresponding 2,4-di-and 2,3,4-trisubstituted pyrroles, only in the case of acetoxime the isomer ratio is ca 1:1. For oximes of methyl isopropyl ketone and pinacolone, the 4-methyl-isomers become predominant (78, 83%, respectively).

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