Abstract According to X-ray diffraction data, N, N'-disulfinyl-1, 2-diaminobenzene in crystal exists as a planar Z, Z isomer. On heating or under the action of catalytic amounts of water, as well as in reactions with LiN (SiMe 3) 2 or PCl 5 in 1: 1 or 1: 2 molar ratios it quantitatively converts into 2, 1, 3-benzothiadiazole. According to 1 5 N NMR data, this transformation is accompanied by deshielding of the nitrogen atoms by 18 ppm.
