Phosphorus Thiophosphorus compounds

Thiophosphorus compounds and their reactions have been studied. Phenols such as 4-tert-butylphenol with red phosphorus and sulphur in equivalent amount heated from 150 to 220X in 8.5 hours gave tri(4-tert-butylphenyl)thionophosphate in 93% yield (ref.40). 

There have apparently been no recent developments in reagents for desulphurizing sulphoxides that use pentavalent phosphorus compounds. Reagents that were reviewed in 1984 include phosphorus pentasulphide, thiophosphoryl bromide, Lawesson s reagent (1), and phosphorus pentachloride in the presence of a trap for CD ions. The traps used included an enamine or an N, JV-dialkylaniline. Presumably, the net effect of this reaction is to generate phosphorus trichloride in situ. The three thiophosphorus reagents obviously function because the P=S bond is some 150 kJ moD weaker than the P=0 bond . 

W. Gerrard and H.R. Hudson, Organic phosphorus and thiophosphorus derivatives, in G.M. Kosolapoff and L. Maier, Eds., Organic Phosphorus Compounds, Vol. 5, WUey, 1973. 

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