Preparation of Esters of Phosphoric Acid by the Reaction of Trivalent Phosphorus Compounds with Diethyl Azodicarboxylate in the Presence of Alcohols

Abstract

Trivalent phosphorus compounds, phosphine or trialkylphosphites, have been oxidized by means of diethyl azodicarboxylate and either benzyl or allyl alcohol to give the corresponding phosphine oxide or trialkyl phosphates. The reaction was then extended to the phosphorylation of alcohols. When allyl diethyl phosphite was treated with diethyl azodicarboxylate in the presence of an alcohol at room temperature, a corresponding alkyl diethyl phosphate and diethyl N-allyl hydrazodicarboxylate were obtained in good yields. On the other hand, when phenol was treated with allyl diethyl phosphite and diethyl azodicarboxylate, diethyl phenyl phosphate, allyl phenyl ether and diethyl hydrazodicarboxylate were obtained. The mechanism of their formation will also be discussed.

A Facile One-Pot Benzylation of Sodium Enolates Using Trifluoromethanesulfonic Anhydride and Diphenyl Sulfoxide

“…For example, O-monobenzylated, Cmonobenzylated and C-dibenzylated products (5 : 45 : 50) were obtained by benzylation of ethyl acetate with benzyl bromide in dimethyl sulfoxide. 4) C-Alkylation of active methylene compounds with alcohols has recently been accomplished in a redox reaction system by Mitsunobu-type reactions, 5) and Tsunoda and coworkers 6) have also reported efficient methods for alkylation of active methylene compounds. However, with benzyl alcohol, it is reported that the concomitant double alkylation and/or an ether forming-reaction takes place.…”

Synthesis of novel dendritic molecules based on pyrroloanthracene units

“…It is well known that products of this type can be formed upon treatment of benzyl and allyl alcohols with DEAD and PPh 3 in the absence of a good nucleophile. 11 It is evident, however, that there is no reason why our AB 2 monomer 10i would show a lack of reactivity. Therefore, we think the extreme activation of benzyl alcohol 12 is likely to facilitate the formation of 16 to a notable extent.…”

Hendrickson Reagent (Triphenylphosphonium Anhydride Trifluoromethane Sulfonate)

“…[2][3][4] These reactions occur in a manner that is analogous to the Mitsunobu reaction, involving an intermediate alkoxyphosphonium salt. 5,6 The advantages of the Hendrickson reagent over the Mitsunobu reagent are that the recovered triphenylphosphine oxide may be recycled by treatment with trifluromethanesulfonic anhydride, the use of explosive azodicarboxylates is not required and competing side reactions are avoided. 7 Furthermore, a number of methods have recently been reported that can easily overcome, or avoid, the formation and removal of the double-stoichiometric amount of triphenylphosphine oxide, a common problem of phosphine-based dehydrating agents.…”