SYNTHESIS OF BIS-STANNYLACETYLENES FROM CALCIUM CARBIDE - ASSISTED BY ULTRASOUND

Seven bis-stannylacetylenes have been prepared from the reaction of calcium carbide with a trisubstituted stannyl halide (R3SnX: R=methyl, ethyl, n-propyl, n-butyl, phenyl, benzyl, cyclohexyl; X=chloride, bromide) in dimethylformamide. The reactivity of the calcium carbide was enhanced using ultrasound generated from a cleaning bath. The products have been characterized by physical constants, elemental analysis, 1H NMR and 13C NMR. When allowed to react for similar time periods, stannyl chlorides and bromides, with identical organic substituents, gave similar yields, suggesting that the reaction does not proceed by an SN2 displacement of halide by carbide. Reactions with triethylgermyl chloride and triethylplumbyl chloride were also observed but the products were not isolated. © 1990, Taylor & Francis Group, LLC. All rights reserved.