Organophosphorus compounds–XVIII : The reaction of alkyl phosphites with 4-triphenylmethyl-1,2-benzoquinone

Dialkyl phosphites react with 4-triphenylmethyl-1,2-benzoquinone (6) to give dihydroxyphosphonates having structure (7). Trialkyl phosphites, on the other hand, attack the carbonyl oxygen of 6, yielding cyclic unsaturated pentaoxyphosphoranes (17). These are converted into the o-quinol phosphate esters (16) by hydrogen chloride.Possible reaction mechanisms are considered and the structural assignments are based on chemical and spectroscopic evidence.