I. B. Rozentsveig, A. Popov, E. Kondrashov
Jun 9, 2009
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Influential Citations
4
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Journal
Russian Journal of Organic Chemistry
Abstract
The reaction of hydrazine with dichalcogenides in aqueous alkaline medium is known to result in reductive cleavage of dichalcogenides giving thiols [1] and other chalcogenols [2], and hydrazine therewith is oxidized into nitrogen. We found that the reaction of dibenzyl disulfide with excess hydrazine hydrochloride in DMF in the presence of sodium or potassium carbonates at heating to 100°C unexpectedly afforded benzalazine. The process was accompanied by hydrogen sulfide evolution. It is presumable that under the conditions of the reaction the dibenzyl disulfide suffered 1,2-elimination with the formation of benzylthiol and thiobenzaldehyde. The latter underwent condensation with hydrazine to give the final benzalazine that apparently existed in the reaction mixture as thioaminal or hemiaminal, but was isolated at acidifying the reaction mixture in the individual state in 38% indicating a good yield of the intermediate thioaldehyde.