performance in the reactions of these substrates, while in silico calculations shed light on the origin of these improvements. Finally, 10 α-fluorocarboxylic acids and 10 α-hydroxycarboxylic acids were prepared on a gram scale via kinetic resolution enabled by WT, W185T, or W185N. This work expands the biocatalytic toolbox and allows a deep insight into the fluoroacetatedehalogenase catalyzed C–F cleavage
Investigating Substrate Scope and Enantioselectivity of a Defluorinase by a Stereochemical Probe
作者:Jian-bo Wang、Adriana Ilie、Shuguang Yuan、Manfred T. Reetz
DOI:10.1021/jacs.7b06019
日期:2017.8.16
reaction by Asp110 pertains. The high preference for the (S)-substrate is of synthetic value. Wide substratescope of RPA1163 in such hydrolytic kinetic resolutions can be expected because the reaction of the even more sterically demanding rac-2-fluoro-2-benzyl acetic acid proceeded similarly. Substrate acceptance and stereoselectivity were explained by extensive molecular modeling (MM) and molecular
Kinetic Resolution of α-Substituted Alkanoic Acids Promoted by Homobenzotetramisole
作者:Xing Yang、Vladimir B. Birman
DOI:10.1002/chem.201101028
日期:2011.9.26
classes of substrates, namely, α‐aryl‐, α‐aryloxy/alkoxy‐, α‐halo‐, α‐azido‐, and α‐phthalimido‐alkanoicacids. Under similar conditions, α‐(arylthio/alkylthio)‐alkanoicacids undergo dynamickineticresolution providing corresponding esters in up to 92 % ee and up to 93 % yield.
An Unusual Conformation of α-Haloamides Due to Cooperative Binding with Zincated Porphyrins
作者:Marina Tanasova、Qifei Yang、Courtney C. Olmsted、Chrysoula Vasileiou、Xiaoyong Li、Mercy Anyika、Babak Borhan
DOI:10.1002/ejoc.200900089
日期:2009.9
with a zinc porphyrin leads to an unprecedented conformation for the determination of the absolute stereochemistry of α-haloamides (α-halocarboxylic acids derivatized with 1,4-phenylenediamine) through the use of exciton-coupled circular dichroism (ECCD). With the use of chiral lactams, whose rotomeric contributions are minimized, both ECCD and NMR spectroscopy demonstrate that the porphyrin favors binding
Cobalt-Catalyzed Asymmetric Hydrogenation of α,β-Unsaturated Carboxylic Acids by Homolytic H<sub>2</sub> Cleavage
作者:Hongyu Zhong、Michael Shevlin、Paul J. Chirik
DOI:10.1021/jacs.9b13876
日期:2020.3.18
The asymmetrichydrogenation of α, β-unsaturatedcarboxylicacids using readily prepared bis(phosphine) cobalt(0) 1,5-cyclooctadiene precatalysts is described. Di-, tri- and tetra-substituted acrylic acid derivatives with various substitution patterns as well as dehydro-α-amino acid derivatives were hydrogenated with high yields and enantioselectivities, affording chiral carboxylicacids including