Reactions of Sulfenamides with Compounds of Trivalent Phosphorus

Abstract

AbstractChloro‐dimethylamino‐phenyl‐p‐tolylthio‐phosphonium chloride 2, dimethylamino‐diphenyl‐p‐tolylthio‐phosphonium chloride 3, bis(diethylamino)‐dimethylamino‐p‐tolylthiophosphonium chloride 4 and tert‐butyl‐dimethylamino‐phenyl‐p‐tolylthio‐phosphonium chloride 5 were prepared by the reaction of N,N‐dimethylamino‐p‐tolylsulfenamide 1 with PhPCl2, Ph2PCl, (Et2N)2PCl and tBu(Ph)PCl, respectively. The reaction of N,N′‐dimethyl‐N,N′‐bis(trimethylsilyl)urea 9 and N‐methyl‐N′‐phenyl‐N,N′‐bis(trimethylsilyl)urea 10 with phenylsulfenyl chloride 6 or p‐nitrophenylsulfenyl chloride 8 furnished the N‐arylthio‐N,N′‐diorgano‐N′‐(trimethylsilyl)‐ureas 11 – 14. The reaction of 11 – 14 and of the previously known compounds 15 and 16 with MePCl2, ClCH2PCl2, tBuPCl2 and PhPCl2 resulted in the formation of the 2‐arylthio‐2‐chloro‐1,2,3‐triorgano‐1,3,2λ5‐diazaphosphetidin‐4‐ones 17 – 26. 1,3‐Dimethyl‐2‐(1,1,1,3,3,3‐hexafluoro‐2‐propoxy)‐2‐phenyl‐2‐phenylthio‐1,3,2λ5‐diazaphosphetidin‐4‐one 29 and the 2‐arylthio‐1,3‐dimethyl‐2‐(p‐nitrophenoxy)‐2‐organyl‐1,3,2λ5‐diazaphosphetidin‐4‐ones 30 – 32 were obtained in the reactions of compounds 17, 24 and 27 with 1,1,1,3,3,3‐hexafluoro‐2‐propanol or p‐nitrophenol in the presence of triethylamine. The reaction of compound 21 with thiophenol in the presence of triethylamine resulted in a mixture of products, from which 1,3,4,5,7‐pentamethyl‐1,3,5,7‐tetraaza‐4λ5‐phosphaspiro[3.3]heptan‐2,6‐dione 33 was isolated. The identity and structure of all the new compounds were established by 1H‐, 13C‐ and 31P‐NMR spectroscopy and by elemental analysis. A possible mechanism of reaction of sulfenamides with compounds of trivalent phosphorus is discussed. For the compounds 5a, 32 and 33 X‐ray structure analyses were conducted. The cation of compound 5a involves four‐coordinate phosphorus (essentially tetrahedral geometry) and is a rare example of a P–S single bond in such a system (P–S 207.37(9) pm). In 32 the geometry at phosphorus is distorted trigonal bipyramidal, with axial positions occupied by oxygen and nitrogen atoms. In the spirophosphorane 33 the geometry at phosphorus is intermediate between trigonal bipyramidal and square pyramidal, with essentially planar four‐membered rings.