Enzymes in organic chemistry — 5: First and chemo-enzymatic synthesis of α-aminooxyphosphonic acids of high enantiomeric excess
摘要:
alpha-Acyloxyphosphonates (+/-)-5a and (+/-)-5b, derived from 3-phenylpropionaldehyde and acetaldehyde. were involved by lipase-catalyzed enantioselective hydrolysis. Three of the four chiral, non-racemic alpha-hydroxyphosphonates obtained had 99% ee. the fourth 91%. They were transformed chemically into alpha-aminooxyphosphonic acids. (C) 1997 Elsevier Science Ltd.
Enzymes in organic chemistry — 5: First and chemo-enzymatic synthesis of α-aminooxyphosphonic acids of high enantiomeric excess
摘要:
alpha-Acyloxyphosphonates (+/-)-5a and (+/-)-5b, derived from 3-phenylpropionaldehyde and acetaldehyde. were involved by lipase-catalyzed enantioselective hydrolysis. Three of the four chiral, non-racemic alpha-hydroxyphosphonates obtained had 99% ee. the fourth 91%. They were transformed chemically into alpha-aminooxyphosphonic acids. (C) 1997 Elsevier Science Ltd.
作者:Joyram Guin、Qinggang Wang、Manuel van Gemmeren、Benjamin List
DOI:10.1002/anie.201409411
日期:2015.1.2
The first catalytic enantioselective Abramovreaction is described. The process is based on the utilization of a chiral disulfonimide catalyst, which efficiently avoids the difficulties encountered with metal‐based catalysts. Several functionalized α‐hydroxy phosphonates were synthesized in good yields and with excellent enantiomeric ratios of up to >99:1. The process was shown to be scalable and up
Imidazolium ion tethered TsDPENs as efficient ligands for Iridium catalyzed asymmetric transfer hydrogenation of α-keto phosphonates in water
作者:Mengxia Sun、Joann Campbell、Guowei Kang、Huigang Wang、Bukuo Ni
DOI:10.1016/j.jorganchem.2016.03.010
日期:2016.5
Iridium-catalyzed asymmetric transfer hydrogenation (ATH) of α-ketophosphonates in water. The reaction provided the desired product α-hydroxyphosphonates in moderate to good yields (44–78%) and good to excellent enantioselectivities (up to >99% ee) under mild reaction conditions without adding any surfactants. The enantiomeric excess was determined by 13P NMR by using (−)-cinchonidine as chiral solvating agent
首次,通过使用咪唑鎓离子束缚的TsDPENs作为铱在水中α-酮膦酸酯的铱催化的不对称转移氢化(ATH)的有效配体,开发了一种有效的方法。该反应在不添加任何表面活性剂的条件下,在温和的反应条件下,以中等至良好的收率(44-78%)和良好至出色的对映选择性(高达> 99%ee)提供了所需的产物α-羟基膦酸酯。通过使用(-)-金可尼定作为手性溶剂化剂,通过13 P NMR测定对映体过量,这是一种比手性HPLC更方便的方法。
Asymmetric synthesis of chiral, nonracemic dialkyl-α-, β-, and γ-hydroxyalkylphosphonates via a catalyzed enantioselective catecholborane reduction
作者:Chris Meier、Wolfgang H.G. Laux
DOI:10.1016/0957-4166(95)00132-9
日期:1995.5
A highly enantioselective synthesis of dialkyl alpha-hydroxyphosphonates achieved by a oxazaborolidine catalyzed reduction with catecholborane starting with m-ketophosphonates is described. Both alpha-aryl- and alpha-alkylketophosphonates were reduced using the (S)-enantiomer of the catalyst 4 leading also to the (S)-configuration in the products 2. The reaction gave good chemical yields and excellent enantiomeric excesses (up to >99 % ee).