The structure of 3:3'-dichlorobenzidine

Analysis of the structures of m-tolidine dihydrochloride (Hargreaves & Taylor, 1941) and of 2:2'-dichlorobenzidine (Smare, 1942) has shown that in each of these molecules (I, II) the phenyl rings are rotated from the cis-planar configuration through approximately 36° in opposite directions around the central diphenyl link.