Organosilyl esters of some phosphorus acids: identification of kinetic and thermodynamic isomers
Abstract
The compounds Na[OP(OPri)2] and P(OPri)3 both react with SiPh3Cl to yield the phosphate PO(OPri)2(SiPh3) rather than the phosphite P(OPri)2(OSiPh3): K[OSiPh3] reacts with PCl(OPri)2 to yield this phosphate in a rearrangement reaction, showing that the phosphate is the thermodynamically more stable isomer. Similarly, Na[OP(OPri)2] reacts with SiMe3Cl to yield only the phosphate PO(OPri)2(SiMe3), which is formed also in the rearrangement reaction of Na[OSiMe3] with PCl(OPri)2. The compound [NH2Et2][SSiPh3] reacts with PCl(OPri)2 to yield the more-stable rearranged phosphorothioate P(OPri)2S(SiPh3) rather than the phosphorothioite P(OPri)2(SSiPh3). The salt K[OSiPh3] reacts with PPh2Cl and PCl3 to give the rearranged products PPh2O(SiPh3) and PO(OSiPh3)2(SiPh3) respectively, but Na[OSiMe3] yields respectively PPh2O(SiMe3) and unrearranged P(OSiMe3)3. The salt K[OSiPh3] reacts wrth PCl(OPri)2S to yield only P(OPri)2(OSiPh3)S, identical to the product formed by reaction of Na[OSP(OPri)2] with SiPh3Cl: on reaction with PClO(OPri)2, [NH2Et2][SSiPh3] gives PO(OPri)2(SSiPh3) at room temperature, but on reflux in toluene forms the rearranged isomer P(OPri)2(OSiPh3)S which is therefore the more-stable isomer.
Please wait while we load your content...
