Synthesis, structural, and spectral studies of N,N′-bis- (5-methylsalicylidene)-2,2′-diamino-4-4′-di-(trifloromethyl) -diphenyl disulfide

A new disulfide compound N,N′-bis-(5-methylsalicylidene)-2,2′- diamino-4-4′-di-(trifloromethyl)-diphenyl disulfide (C ₃₀ H ₂₂ F ₆ N ₂ O ₂ S ₂ ) was prepared and characterized by ¹ H-NMR, IR, mass spectroscopy, and single-crystal X-ray diffraction. Spectroscopic assignments and the crystallographic results indicate the predominance of the phenol-imine tautomeric form. [For example, N=C double bonds 1.274(9)Å and 1.275(9)Å, two very close hydrogen peaks to the atomic positions of O atoms in difference Fourier map and two strong intramolecular hydrogen bonds (O-H⋯N) with O⋯N distances of 2.611(10) and 2. 613(8) Åstrongly indicate that this tautomeric form is preferred]. The strong effect of the para CF ₃ groups in the molecular and crystallographic arrangement was attributed to the electronegativity of the CF ₃ groups.