97070-79-6Relevant articles and documents
Combining Photo-Organo Redox- and Enzyme Catalysis Facilitates Asymmetric C-H Bond Functionalization
Zhang, Wuyuan,Fueyo, Elena Fernandez,Hollmann, Frank,Martin, Laura Leemans,Pesic, Milja,Wardenga, Rainer,H?hne, Matthias,Schmidt, Sandy
supporting information, p. 80 - 84 (2019/01/04)
In this study, we combined photo-organo redox catalysis and biocatalysis to achieve asymmetric C–H bond functionalization of simple alkane starting materials. The photo-organo catalyst anthraquinone sulfate (SAS) was employed to oxyfunctionalise alkanes to aldehydes and ketones. We coupled this light-driven reaction with asymmetric enzymatic functionalisations to yield chiral hydroxynitriles, amines, acyloins and α-chiral ketones with up to 99 % ee. In addition, we demonstrate functional group interconversion to alcohols, esters and carboxylic acids. The transformations can be performed as concurrent tandem reactions. We identified the degradation of substrates and inhibition of the biocatalysts as limiting factors affecting compatibility, due to reactive oxygen species generated in the photocatalytic step. These incompatibilities were addressed by reaction engineering, such as applying a two-phase system or temporal and spatial separation of the catalysts. Using a selection of eleven starting alkanes, one photo-organo catalyst and 8 diverse biocatalysts, we synthesized 26 products and report for the model compounds benzoin and mandelonitrile > 97 % ee at gram scale.
Preparation of chitosan-supported urea materials and their application in some organocatalytic procedures
de Gonzalo, Gonzalo,Franconetti, Antonio,Fernández, Rosario,Lassaletta, José M.,Cabrera-Escribano, Francisca
, p. 365 - 374 (2018/07/25)
An efficient and mild procedure was developed for the preparation of three chitosan-supported ureas containing electron-withdrawing groups. These catalysts were characterized and employed as organocatalysts in different transformations, including the enan
Enantioselective cyanosilylation of aldehydes catalyzed by a multistereogenic salen-Mn(III) complex with a rotatable benzylic group as a helping hand
Wei, Yun-Long,Huang, Wei-Sheng,Cui, Yu-Ming,Yang, Ke-Fang,Xu, Zheng,Xu, Li-Wen
, p. 3098 - 3103 (2015/02/02)
A multistereogenic salen-Mn(iii) complex bearing an aromatic pocket and two benzylic groups as helping hands was found to be efficient in the catalysis of asymmetric cyanosilylation. The salen-Mn catalyst partially mimics the functions of biocatalysts by