Reaction of aryl aldehydes with thiocyanates in the presence of tributylphosphine

Abstract

Aryl aldehydes react with methyl thiocyanate in the presence of tributylphpsphine to afford S-methyl thiobenzoates and arylacetonitriles in good yields. This is a novel disproportionation reaction involving carbon–carbon bond formation. These compounds thus obtained are easily converted into deoxy-benzoins using sodium hydride. On the other hand, p-dialkylaminobenzaldehydes react with methyl thiocyanate under the same conditions to furnish both the corresponding trans-dicyanostilbenes and succinonitriles in moderate yields. Finally, the reaction was carried out with aryl thiocyanates resulting in the formation of addition products.