Phosphoryl disulphides, synthesis

Phosphoryl disulphides, compounds which possess the P(Z)SSP(Z) moiety (Z = O or S), are obtained most readily through the mild oxidation of the sodium thioates RR P(Z)SNa with iodine in KI solution. An alternative synthesis is based in the chlorination of the free thioic acid, conveniently with SO2CI2 the (+)- and (-)-forms of the disulphide 116(Z = O) are formed from the (R)-(+)- and (5)-(-)-forms of the precursor acid Further chlo-rinolysis with more sulphuryl chloride then cleaves the disulphide bond with the formation of (+)- and (-)-ethoxyethylphosphinoylsulphenyl chloride (117 Z = 0)1 ". A similar... 

The use of triphenylphosphine and 2,2 -bipyridyl disulphide in oxidation-reduction condensations has been extended to the phosphorylation of alcohols and phosphates, and to the preparation of 5 -(2-pyridyl) phosphorothioates (60) which have been used for the synthesis of pyrophosphates (see Chapter 6, Section 1). 

The reaction of dipyridyl disulphide with triphenylphosphine to give the stable phosphonium salt (51) has been used in new methods of phosphorylation (reaction A), in peptide synthesis (reaction B), and in the formation of active esters of cx-amino-acids (reaction C). These reactions appear to have synthetic potential. 

Further use has been made of the reaction of disulphides with tervalent phosphorus compounds in phosphorylation reactions, e.g. in the synthesis of (57).68... 

---