A Convenient (E)-Stereoselective Synthesis of Alkenylphosphonates
摘要:
Diethyl (E)-alkenylphosphonates have been prepared stereoselectively by dehydration of the corresponding beta-hydroxyphosphonates using DCC/CuCl2 in refluxing toluene. Starting beta-hydroxyphosphonates were obtained in high yield from diethyl methylphosphonate.
The contra-thermodynamic isomerization of α- and β-substituted cinnamate derivatives catalyzed by the Cu(OAc)2/rac-BINAP complex under blue light irradiation is reported. The use of an oxazolidinone template, which favored the complexation of the copper catalyst to the substrate, allowed the E → Z isomerization of the catalytically formed chromophore under simple and robust reaction conditions in good
An efficient and novel method was developed towards the synthesis of alkenylphosphonates from simple olefins and phosphonate diesters. This method was enabled by the use of cheap and commercially available silver salts and TEMPO. This method exhibits of good functional group tolerance, specific (E)‐selectivity for all olefins and vinyl‐selectivity for aliphatic olefins. A radical mechanism was proposed
Halodephosphorylation of α,β-unsaturated phosphonic acid monoesters
作者:Hind Lahrache、Sylvie Robin、Gérard Rousseau
DOI:10.1016/j.tetlet.2005.01.089
日期:2005.3
Reaction of α,β-ethylenic and acetylenic phosphonicacidmonoesters with (biscollidine)iodine(I) or (biscollidine)bromine(I) hexafluorophosphate led to α,β-unsaturated halides by, without precedent, dephosphorylation reactions.
Cu(<scp>i</scp>)/Fe(<scp>iii</scp>)-Catalyzed C–P cross-coupling of styrenes with H-phosphine oxides: a facile and selective synthesis of alkenylphosphine oxides and β-ketophosphonates
作者:Jian Gu、Chun Cai
DOI:10.1039/c7ob00505a
日期:——
Cu(I)/Fe(III)-Catalyzed phosphorylation and oxyphosphorylation of styrenes with H-phosphonates which can be controlled by varying the reaction temperature are developed. This study offers a new and expedient strategy for the synthesis of useful alkenylphosphine oxides and β-ketophosphonates in satisfactory yields. Moreover, the transformation is proposed to proceed via a radical process and exhibits
The first asymmetrichydrogenation of β,β-diaryl unsaturated phosphonates has been realized for synthesis of β,β-diaryl chiralphosphonates with excellent enantioselectivities (up to 99.9% ee) catalyzed by the Rh-(R,R)-f-spiroPhos complex. Furthermore, this catalyst also exhibits comparably excellent performance for β-aryl-β-alkyl unsaturated phosphonates providing the corresponding chiral phosphonates
首次实现了β,β-二芳基不饱和膦酸酯的不对称氢化,用于在Rh-( R , R )-f-spiroPhos 络合物催化下合成具有优异对映选择性(高达99.9% ee)的β,β-二芳基手性膦酸酯. 此外,该催化剂对 β-芳基-β-烷基不饱和膦酸酯也表现出相当优异的性能,提供相应的手性膦酸酯,其 ee 值高达 99.9%。这种方法为不对称合成手性膦酸盐提供了一种直接的途径。