Intramolecular Chalcogen−Nitrogen Interactions: Molecular and Electronic Structures of Geometrical Isomers of the Diazenes RSNC(R‘)NNC(R‘)NSR

The sulfur-containing diazenes ArSNC(Ar‘)NNC(Ar‘)NSAr (1d, Ar = Ar‘ = 4-CH3C6H4; 3b, Ar = Ph, Ar‘ = 2-BrC6H4; 3c, Ar = Ph, Ar‘ = 2-CF3C6H4) are obtained by the reaction of Ar‘CN2(SiMe3)3 with 3 molar equivs of ArSCl in CH2Cl2. X-ray structural determinations have shown that 1d exists as a Z,E,Z isomer with a weak intramolecular S···N interaction [2.607(10) Å], whereas 3b adopts an E,E,E configuration. Crystals of 1d are monoclinic, space …