?-Alkylthio-substituted ?, ?-unsaturated aldehydes

Abstract

1. The reaction of sodium alkanethiolates with the acetals of α-halo-substituted α, β-unsaturated aldehydes leads to the correspondingβ-alkylthio-substituted derivative independent of the nature of the halogen or of the presence of an alkyl group in theβ position, and also independent of the character of the employed solvent. 2. In acid medium theβ-alkylthio-substituted acetals ofα, β-unsaturated aldehydes are hydrolyzed at room temperature without cleaving the C-S linkage to give the correspondingβ-alkylthio-substitutedα, β-unsaturated aldehydes. The latter under mild conditions form derivatives at the carbonyl group without changing the carbon skeleton. This reaction when run with heating leads to cyclization and the formation of pyrazole derivatives. Prolonged heating of the butylthioacrolein with excess butanethiol leads to the reaction product at the two reaction centers, and specifically to 1,1,3,3-tetrabutylthiopropane.