X-ray structural analysis of two isomeric modifications of 1,3-diphenyl-2-(phenylazo)propene

Abstract

The structures of two isomers of 1,3-diphenyl-2-(phenylazo)propene have been determined by X-ray crystallography. The trans-isomer (I) has Z= 4, a= 27·50, b= 5·62, c= 11·16 Å, β= 90° 30′, space group P2₁/a. The cis-isomer (II) has Z= 2, a= 12·33, b= 8·03, c= 8·45 Å, β= 92° 6′, space group P2₁. The structures were refined to R 0·122 [(I), 2036 reflections] and 0·113 [(II), 1732 reflections]. Slight difference in molecular conformation and crystal packing are discussed.