The stereochemistry of some α,β-Di-(2-thienyl)acrylonitriles and β,β'-Di-(2- thienyl)-α,α'-(2,5-thiophen)diacrylonitriles

Abstract

It has been shown that condensation of thiophen-2-aldehyde with 2-thienyl- acetonitrile gives trans-α β-di-(2-thienyl)acrylonitrile; but condensation of thiophen- 2-aldehyde with 2-thienylacetic acid yields cis-α,β-di-(2-thienyl)acrylic acid. Similarly, condensation of thiophen-2-aldehydes with 2,5-biscyanomethylthiophen gave trans-trans-β,β'-di-(2-thienyl)-α,α'-(2,5-thiophen)diacrylonitriles; but condensation with thiophen-2,5-diacetic acid gave cis-cis-β,β'-di-(2-thieny1)-α,α'-(2,5-thio-phen)diacrylic acids.