[EN] STEREOSELECTIVE SYNTHESIS OF HIGHLY SUBSTITUTED ENAMIDES<br/>[FR] SYSNTHÈSE STÉRÉOSÉLECTIVE D'ÉNAMIDES À FORTE SUBSTITUTION
申请人:UNIV NANYANG TECH
公开号:WO2012173572A1
公开(公告)日:2012-12-20
The disclosure provides new methods for the oxidative Heck cross-coupling reaction with electron-rich alkenes such as substituted β-amidoacrylate and other related substituted enamides. Previously, functionalization of enamides under Heck conditions has been limited to those with unsubstituted vinyl groups. By tuning the reaction parameters that allow for the balance between stability and reactivity of the reactants, the oxidative Heck cross-coupling reaction now provides highly substituted enamides in good to excellent yields. (II) (III) (I)·
Practical P-Chiral Phosphane Ligand for Rh-Catalyzed Asymmetric Hydrogenation
作者:Duan Liu、Xumu Zhang
DOI:10.1002/ejoc.200400690
日期:2005.2
conformationally rigid P-chiral bis(trialkylphospholane) ligand 2 (DuanPhos) has been prepared in both enantiomeric forms through a concise syn-thesis. Rh-2 complex has exhibited remarkably high enantio-selectivities (up to >99% ee) and reactivities (up to 10,000 TON) for the hydrogenation of a wide variety of functionalized prochiral alkenes (5 different types), which provides a very practical catalytic system
[EN] E-ISOMERIC beta-AROMATIC OR HETEROAROMATIC SUBSTITUTED beta-ACYLAMINO-ACRYLATES AND METHODS OF PREPARING THE SAME<br/>[FR] DOLLAR G(B)-ACYLAMINO-ACRYLATES E-ISOMERES A SUBSTITUTION DOLLAR G(B)-AROMATIQUE OU HETEROAROMATIQUE ET LEUR PROCEDES DE PREPARATION
申请人:DSM IP ASSETS BV
公开号:WO2004011414A1
公开(公告)日:2004-02-05
E-isomeric ß-(hetero) aromatically substituted acylaminoacrylates are of great economic interest since with them, by means of hydration, precursors of appropriately substituted (ß-amino acids can be prepared and, by doing so, lead to higher enantio-selectivities than the corresponding Z-isomers. The invention describes novel E-isomeric R-aromatically or ß-heteroaromatically substituted ß-acylaminoacrylates of the general formula (I): in which R represents hydrogen or a substituted or unsubstituted alkyl or aromatic or heteroaromatic residue, and R' represents a substituted or unsubstituted aromatic or heteroaromatic residue, R' represents H, a substituted or unsubstituted alkyl or aromatic or heteroaromatic residue, and R'' represents H, a substituted or unsubstituted alkyl, acyl, aromatic or heteroaromatic residue. According to the invention, the compounds according to the general formula (I) are prepared by acylation at temperatures below the boiling point of the reaction mixture.
complexes were highly efficient catalysts for asymmetrichydrogenation of β-aryl-substituted β-(acylamino)acrylates and β-aryl-substituted β-keto esters. The Ru-bisphosphinite catalysts can tolerate an E/Z mixture of β-aryl-substituted β-(acylamino)acrylates. These highly enantioselective hydrogenations provide a useful way to prepare β-aryl-substituted β-amino acids and β-hydroxyl acids.
Nickel-Catalyzed Asymmetric Transfer Hydrogenation of Olefins for the Synthesis of α- and β-Amino Acids
作者:Peng Yang、Haiyan Xu、Jianrong Steve Zhou
DOI:10.1002/anie.201407744
日期:2014.11.3
The field of asymmetric (transfer) hydrogenation of prochiral olefins has been dominated by noble metal catalysts based on rhodium, ruthenium, and iridium. Herein we report that a simple nickel catalyst is highly active in the transfer hydrogenation using formic acid. Chiral α‐ and β‐amino acid derivatives were obtained in good to excellent enantioselectivity. The key toward success was the use of