183874-10-4Relevant academic research and scientific papers
Methylenethioxophosphorane (thiophosphene) intermediates in the reactions of diphenylmethylphosphonamidothioic chlorides with amines. Differences between the elimination-addition mechanisms of nucleophilic substitution for P=S and P=O substrates
Harger, Martin J.P.
, p. 489 - 493 (2002)
In reactions with R2NH (R = Me or Et) in CHCl3 the P=S substrate Ph2CHP(S)(NMe2)Cl differs markedly from its P=O counterpart: the rate of substitution is increased much more by a 4-nitro substituent but is also more sensitive to the bulk of the amine, there is greater discrimination between competing nucleophiles, and with R2ND there is relatively little H-D exchange at the α carbon atom prior to substitution. Yet the P=S and P=O compounds both seem to react by elimination-addition mechanisms. It is suggested that whereas in the P=O case the conjugate base is formed rapidly and elimination of chloride to give the methyleneoxophosphorane (phosphene) intermediate is rate limiting, the conjugate base of the P=S substrate eliminates chloride rapidly giving a relatively stable methylenethioxophosphorane (thiophosphene) intermediate.
Nucleophilic substitution in benzylic phosphonothioic dichlorides formation of a diamide without intervention of the amidic chloride
Harger, Martin J.P.
, p. 8247 - 8248 (2007/10/03)
The diamide RP(S)(NEt2)2 (R = PhCH2 or Ph2CH) is formed directly from the dichloride RP(S)Cl2 more quickly than it is from the amidic chloride RP(S)(NEt2)Cl.
