Substituent Effect on the cis-trans Photoisomerization of trans,trans,trans-1,6-Diphenyl-1,3,5-hexatrienes

Abstract Quantum yield of trans,trans,trans→cis,trans,trans photoisomerization of p,p′-disubstituted 1,6-diphenyl-1,3,5-hexatriene increased as the polarity of substituents increased, regardless of their electron-withdrawing or donating nature. On the contrary, quantum yield of trans,trans,trans→trans,cis,trans isomerization increased with increasing the electron-donating nature of substituents.