Pratibha Sharma, Ashok Kumar, Manisha Sharma
Aug 2, 2005
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Influential Citations
7
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Journal
Journal of Molecular Catalysis A-chemical
Abstract
The insertion of dimethylvinylidene carbene into azo moiety was investigated in order to synthesize 4,6-dimethyl-5-[2-(2-methylprop-1-enyl)-1H-benzimidazol-1-yl] pyrimidine-2(5H)-thiones [7a–j] under kinetically controlled phase transfer catalysis conditions. In situ generation of dimethylvinylidene carbene was facilitated by the interaction between 3-chloro-3-methyl-1-butyne and alkali at the interface. Interestingly, insertion of this carbene into the NN linkage of 2,4-dimethyl-3-arylazo-6-thiopyrimidine afforded newly synthesized desired benzimidazolo pyrimidines. The reaction follows the pseudo-first order rate law. Rational mechanism of the reaction is proposed according to the experimental evidence. The compounds were synthesized in excellent yields (70–80%) and their structures were established on the basis of their IR and 1H NMR spectral data.