Phosphanes reaction with phosgene

The story of the reaction of isocyanide dichlorides with bis(trimethylsilyl)phenylphosphane, however, does not end here. Like the reaction of t-butyl-bis(trimethylsilyl)phosphane with phosgene, the conversions with isocyanide dichlorides depend very much upon the reaction conditions. If the reaction is carried out at ambient temperature in a molar ratio of 1 1 in such a way that the isocyanide dichloride is rapidly dropped into the phos-phane solution, the hitherto unknown, 2,4-bis(phenylimino)-l,3-diphenyl-1,3-diphosphetanes are obtained besides the phosphinomethylenephosphanes. Several findings, suggest that their... 

The intermediate 1,3-diphosphapropenes can be synthesized in a separate reaction of bis(trimethylsilyl)phosphanes with phosgene or isocyanide dichlorides (29, 99), respectively, and can be converted to the unsymmetrically substituted pentadienes with phosphaketene [Eq. (47)]. 

In this lecture some new routes to phosphorus-carbon compounds with P-C multiple bonds, found in connection with our investigations on reactions of tertiary phosphanes with chlorinated carbon compounds, such as tetrachloromethane, hexachloroethane, phosgene, and isocyanide dichlorides are reported. Furthermore some stereochemical problems concerning this type of compound will be discussed. 

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