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The Abramov and Pudovik reactions are the related conversions of trialkyl and dialkyl phosphites (respectively) to α-hydroxy phosphonates in the presence of carbonyl compounds. Both reactions proceed by similar mechanisms involving the attack of the nucleophilic phosphorus atom on the carbonyl carbon. They are named after Russian chemists Vasily Abramov (1904–1968) and Arkady Pudovik (1916–2006).〔(Аркадий Николаевич Пудовик ). iopc.ru〕 ==Introduction== Electron-rich sources of phoshorus such as phosphites, phosphonites, and phosphinites may undergo nucleophilic addition to carbon atoms in simple carbonyl compounds. When fully esterified phosphites are used (Abramov reaction), neutralization of the resulting tetrahedral intermediate usually occurs via the transfer of an alkyl or silyl group from an oxygen attached to phosphorus to the newly created alkoxide center. Conjugate addition is also possible, and gives γ-functionalized carbonyl compounds or enol ethers after group transfer. The use of siloxy-containing phosphorus sources has greatly expanded the scope of this reaction, as the resulting α-siloxy compounds can be converted into the corresponding α-hydroxy derivatives in the presence of an alcoholic solvent ''(1)'' The Pudovik reaction employs dialkyl phosphites under basic conditions, which add to carbonyl compounds upon deprotonation to yield α-hydroxy phosphonates. Group transfer is not necessary in this case, as neutralization of the tetrahedral intermediate occurs via proton transfer. A catalytic, enantioselective variant of the Pudovik reaction has recently been developed. ''(2)'' 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Abramov reaction」の詳細全文を読む スポンサード リンク
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