Dioxirane oxidation of substituted vinylphosphonates: a novel efficient route to 1,2-epoxyalkylphosphonates
摘要:
A new stereoselective route to substituted 1,2-epoxyalkylphosphonates through oxidation of corresponding alk-1-enylphosphonates by 'in situ' generated ethylmethyldioxirane is described. (C) 1998 Elsevier Science S.A. All rights reserved.
organolithium to 1-alkynylphosphonates (1) afforded vinylphosphonates and enamine phosphonates (2) in good to excellent yields. The reaction was carried out in dry THF at low temperature and proved to be completely stereoselective (syn addition). Alkyl, aryl, and haloalkyl groups were attached to the alkynyl entity, so the resulting vinylphosphonates contained various functional groups. The stereochemistry
Stereoselective syntheses of mono-, di- and trisubstituted diethyl alk-l-enylphosphonates, starting from readily available alk-1ynylphosphonates, have been developed, using catalytic hydrogenation or cuprate addition on the triple bond.
A new stereoselective route to substituted 1,2-epoxyalkylphosphonates through oxidation of corresponding alk-1-enylphosphonates by 'in situ' generated ethylmethyldioxirane is described. (C) 1998 Elsevier Science S.A. All rights reserved.