182175-26-4Relevant articles and documents
Fragmentation of a phenylphosphonamidic acid as a new technique for the generation of phenyl dioxophosphorane
Quin, Gyoengyi Szakal,Jankowski, Stefan,Quin, Louis D.
, p. 93 - 98 (1996)
N-(1-Adamantyl) phenylphosphonamidic acid (3), an easily prepared solid, on heating in toluene or 1,2-dichloroethane gave the crystalline adamantylamine salt of the anhydride PhP(O)(NHAd)-O-PPh(O)(OH). The mechanism is proposed to involve first the fragmentation of 3 to form phenyl dioxophosphorane, PhPO2, which then acts as a phosphorylating agent to unreacted 3. This mechanism was supported by the observation of first-order kinetics for the consumption of 3. When the phosphonamidic acid was fragmented in the presence of an alcohol, the intermediate PhPO2 was trapped as the monoalkyl phenylphosphonate. The OH groups on the surface of silica gel were also phosphonylated by PhPO2. The acidic OH group of a phosphoric acid monoester (thymyl phosphate) was phosphonylated to give Thy-O-P(O)(OH)-O-PPh(O)(OH). It is concluded from this study that N-(1-adamantyl) phenylphosphonamidic acid is a useful precursor of phenyl dioxophosphorane, which can perform valuable phosphonylation operations.
