Addition of elemental selenium to phosphonate carbanions- - a key step in the synthesis of vinylphosphonates. A new synthetic approach to 1,4-dicarbonyl systems.
A convenient synthesis of vinylphosphonates which involves addition of elemental selenium to phosphonate carbanions followed by alkylation and selenoxide elimination is described. A general approach to 1,4-dicarbonyl systems based on diethyl α-methylthiovinylphosphonate is also reported.
MIKOLAJCZYK, M.;GRZEJSZCZAK, S.;KORBACZ, K., TETRAHEDRON LETT., 1981, 22, N 32, 3097-3100
作者:MIKOLAJCZYK, M.、GRZEJSZCZAK, S.、KORBACZ, K.
DOI:——
日期:——
Phosphonates containing sulfur and selenium. Synthesis of vinylphosphonates bearing α-sulfenyl, α-selenenyl, α-sulfinyl and α-seleninyl moieties and studies on nucleophilic addition
作者:Wanda H. Midura、Jerzy A. Krysiak
DOI:10.1016/j.tet.2004.10.026
日期:2004.12
efficiently to α-phosphorylvinyl sulfoxides or α-phosphorylvinyl selenides depending on the reaction conditions. Oxidation of α-phosphorylvinyl selenides and subsequent thermolysis of selenoxides afford alkynylphosphonates. Studies of the stereochemical course of nucleophilic addition to α-phosphoryl sulfoxides show high facial stereoselectivity of the reaction, however, epimerisation at the α-carbon atom leads