Synthesis, crystal structure, and NMR spectroscopy of a 1,3,2?5,4?5-oxathiadiphosphetane

Abstract

From the crude product of the synthesis of the dithiadiphosphetane [RP(S)S]2 (with R = 2,4,6-iPr3C6H2), the trans-oxathiadiphosphetane has been isolated, C30H40OP2S3. X-ray structure analysis and mass spectroscopic investigations give unequivocal evidence for this structure: monoclinic, C2/c (no. 15), a = 13.066(8), b = 21.726(8), c = 12.070(6) Å, β = 103.54(10)°, V = 3331 Å3, Z = 4, and Dc = 1.158 g/cm3. The asymmetric unit consists of half the formula unit. Solid-state 31P NMR spectra give information about the chemical shift anisotropy. Results of IGLO calculations of the 31P nuclear magnetic shielding tensor agree satisfactorily with the experimental data. Monitoring the reaction of several dithiadiphosphetanes with benzophenone in solution by 31P NMR spectroscopy indicates that additional oxathiadiphosphetanes as well as thiotrimetaphosphonates are present. © 1996 John Wiley & Sons, Inc.