1486-20-0Relevant academic research and scientific papers
Trimethylsilyl esters of phosphorus acids. III. Esters of difluoro- and bis(trifluoromethyl)phosphinous and -thiophosphinous acids
Cavell,Leary,Sanger,Tomlinson
, p. 1374 - 1380 (2008/10/08)
The esters R2PESi(CH3)3 (R = F, E = O; R = CF3, E = O, S) have been prepared using one or more of four synthetic routes (CF3)2PSSi(CH3)3 is the first known example of a PIII-S-Si bridged compound, but the analogous difluoro ester F2PSSi(CH3)3 appears to be thermally unstable at 25°. Attempted syntheses of the P(V) isomers R2P(E)Si(CH3)3 gave only the P(III) forms, indicating that these systems are susceptible to anti-Arbuzov rearrangements. The difference in the stability and polarity between the P-O-Si and P-S-Si bridge units was demonstrated by the reactions of the esters with HCl and (CH3)2NH. At least three different reactions of the esters with dimethylamine were observed: cleavage at the E-Si bond with or without concomitant subsequent reaction of (CH3)3SiN(CH3)2 with the ionic product R2PE- and, in the case of (CF3)2POSi(CH3)3, displacement of CF3H to yield CF3[N(CH3)2]POSi(CH3)3. The latter phosphine showed a temperature-dependent nmr spectrum consistent with conformational isomerism of the N(CH3)2 group.
