Ligand‐Controlled Regiodivergence in Nickel‐Catalyzed Hydroarylation and Hydroalkenylation of Alkenyl Carboxylic Acids**
作者:Zi‐Qi Li、Yue Fu、Ruohan Deng、Van T. Tran、Yang Gao、Peng Liu、Keary M. Engle
DOI:10.1002/anie.202010840
日期:2020.12.14
the ligand environment around the metal center dictates the regiochemical outcome. Markovnikov hydrofunctionalization products are obtained under mild ligand‐free conditions, with up to 99 % yield and >20:1 selectivity. Alternatively, anti‐Markovnikov products can be accessed with a novel 4,4‐disubstituted Pyrox ligand in excellent yield and >20:1 selectivity. Both electronic and stericeffects on the
α-ketoglutarate-dependent aryloxyalkanoate dioxygenases (AADs) are repurposed for applications in biocatalytic oxyfunctionalization. Activity profiling of natural AADs enabled the synthesis of four types of α-and β-hydroxy acids with broad scope, high efficiency, and good selectivity.
A process is described for stereospecifically hydrating crotonobetaine to L-(-)-carnitine via the action of an enzyme produced by four new strains of Proteus mirabilis (NRRL B-18480, NRRL B-18481, NRRL B-18482, and NRRL B-18483) in biotransformation media containing from 10 to 12% (w/v) crotonobetaine inner salt.