STRUCTURAL CHARACTERIZATION OF TRANS-2,4-DITHIO-2,4-DIANILINO-1,3-DIPHENYL-1,3,2,4-DIAZADIPHOSPHETIDINE, [(C6H5NH)P(S)NC6H5]2

Reaction of β-P4S3I2 with aniline results in formation of [(C6H5NH)P(S)NC6H5]2, 1, in moderate yield. The structure of I has been established by spectral data and a single-crystal X-ray analysis as iraw-2, 4-dithio-2, 4-dianilino-l, 3-di-phenyl-1, 3, 2, 4-diazadiphosphetidine. I forms monoclinic crystals in space group P21/c with a = 15.287 (5) Å, β = 8.639 (2) Å, c = 18.728 (5) Å, 0 = 108.97 (2)°, Z = 4, dobsd = 1.39 g cm-1, daU = 1.398 g cm-1 (20 °C, Mo Ka). The structure, solved by direct methods, refined to Rf = 0.062 and RwF = 0.064 for 2127 independent observed reflections. The unit cell of I contains molecules of two slightly different conformational types, A and B, of C(and approximate Cy, symmetries, respectively. The mean ring P—N, exocyclic P—N, and P═S distances are 1.688 (8), 1.670 (6), and 1.905 (4) Å, respectively. The mean ring P-N-P, ring N-P-N, and exo-S-P-N angles are 101.2 (3), 108.5 (4), and 102.3 (3)°, respectively. Comparison of [(C6H5NH)P(S)NC6H5]2 from (C6H5NH)3PS thermolysis with I from the β-P4S3I2-C6HSNH2 reaction indicates that the two are identical. There is no evidence for cis isomeric product in either reaction system. From the reaction of a-P4S3I2 with C6HSNH2, traces of [(C6H5NH)P(S)NC6H5]2 of a possibly different structural form than I are obtained. © 1979, American Chemical Society. All rights reserved.