Copper-Catalyzed Asymmetric Synthesis of Tertiary α-Hydroxy Phosphonic Acid Derivatives with In Situ Generated Nitrosocarbonyl Compounds as the Oxygen Source
作者:Biplab Maji、Hisashi Yamamoto
DOI:10.1002/anie.201408893
日期:2014.12.22
α‐Hydroxy phosphonic acids and their derivatives are highly bioactive structural motifs. It is now reported that these compounds can be accessed through the copper‐catalyzed direct α‐oxidation of β‐ketophosphonates using in situ generated nitrosocarbonyl compounds as an electrophilic oxygen source. These reactions proceeded in high yields (up to 95 %) and enantioselectivities (up to >99 % ee) for both
Enantioselective chlorination and fluorination of β-keto phosphonates catalyzed by chiral Lewis acids
作者:Luca Bernardi、Karl Anker Jørgensen
DOI:10.1039/b415568h
日期:——
The direct chiral Lewis acidic enantioselective chlorination and fluorination of β-keto phosphonates is presented; the chlorination proceeds in high yields and with up to 94% ee using NCS as the chloro source, while the fluorination with (PhSO2)2NF (NFSI) gives the optically active α-fluoro-β-keto phosphonates in moderate to good yields and with up to 91% ee.
An Easy Approach to Optically Active α-Amino Phosphonic Acid Derivatives by Chiral Zn(II)-Catalyzed Enantioselective Amination of Phosphonates
作者:Luca Bernardi、Wei Zhuang、Karl Anker Jørgensen
DOI:10.1021/ja050989v
日期:2005.4.1
A catalytic direct enantioselective electrophilic amination of beta-keto phosphonates has been developed applying chiral bisoxazoline-zinc(II) complexes as the catalyst. The reaction proceeds well for both acyclic and cyclic substrates in high yields and with up to 98% ee using azodicarboxylates as the nitrogen source. The scope of the reaction is, for example, the further transformation to optically active beta-hydroxy-alpha-amino phosphonates with very high stereoselection.