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.
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.
essential building blocks for organophosphorus compounds. However, the asymmetric synthesis of these units remains a significant challenge. Herein, we describe a one-pot chemoenzymatic cascade process to access chiral β-hydroxyphosphonates, which combines photo-oxidative chemical reactions and bioreductions. The incorporation of photooxidation in the chemical reaction resulted in up to 92% yield and
手性 β-羟基膦酸酯是有机磷化合物的重要组成部分。然而,这些单元的不对称合成仍然是一个重大挑战。在这里,我们描述了一种获得手性β-羟基膦酸盐的一锅化学酶级联过程,该过程结合了光氧化化学反应和生物还原。化学反应中光氧化的结合导致级联中 β-羟基膦酸酯的产率高达 92%,对映体过量 (ee) 大于 99%。此外,( S )-(2-羟基-2-苯基乙基)膦酸二乙酯的放大也证明了该策略的潜在应用。
Nonenzymatic kinetic resolution of racemic β-hydroxyalkanephosphonates with a chiral copper catalyst
Kinetic resolution of beta-hydroxyalkanephosphonates was efficiently performed by 2-fluorobenzoylation in the presence of copper(II) triflate and (R,R)-Ph-BOX as a catalyst with good s value of up to 21 (C) 2010 Elsevier Ltd. All rights reserved.