2707-67-7Relevant articles and documents
TRANSFORMATIONS OF DIFLUOROPHOSPHINES: THE INFLUENCE OF SOLVENT ON THE REACTION PATHWAY AND RING SIZE IN CYCLOPOLYPHOSPHINES
Schmutzler, Reinhard,Heuer, Lutz,Schomburg, Dietmar
, p. 149 - 156 (2007/10/02)
The spontaneous transformation reactions of some difluorophosphines in chloroform as solvent are described.First, the redox disproportionation of 2,5-dimethylphenyldifluorophosphine, 1, unexpectedly led to the formation of the cyclopolyphosphine, hexakis-(2,5-dimethylphenyl)cyclohexaphosphine, 2a and 2,5-dimethylphenyltetrafluorophosphorane, 3.Secondly, CF3PF2, 4, was found to undergo a scrambling reaction with formation of (CF3)2PF, 5 and PF3, 6, rather than a redox disproportionation.In contrast, the difluorophosphines, RPF2 with R = 2,4,6-trimethylphenyl,9-anthracenyl, and 9-phenanthryl were found to be stable with regard to such transformations.A single crystal X-ray diffraction study of 2 (as a 1:1 solvate with CDCl3, 2a) was conducted. 2 was found to exist in a chair conformation with a PP bond length of 222.9 pm.The previously known hexamer, (PhP)6, 2b, was formed in the redox disproportionation of a neat sample of PhPF2, held at -20 deg C for several months.Its X-ray crystal structure, first reported in 1965, was redetermined, and served to establish the nature of the product. 2b was found to display a conformation very similar to that of 2/2a.Key words: Difluorophosphines; redox disproportionation; cyclopolyphosphines; X-ray crystal structure.