A novel and facile iron-catalyzed cyclization of ketoximeacetates and aldehydes for the green synthesis of substituted pyridines has been developed. In the presence of a FeCl3 catalyst, the reaction...
4-HO-TEMPO-Catalyzed Redox Annulation of Cyclopropanols with Oxime Acetates toward Pyridine Derivatives
作者:Jun-Long Zhan、Meng-Wei Wu、Dian Wei、Bang-Yi Wei、Yu Jiang、Wei Yu、Bing Han
DOI:10.1021/acscatal.9b00832
日期:2019.5.3
for the synthesis of pyridines through the annulation of cyclopropanols and oxime acetates has been developed. This protocol features good functional group tolerance and high chemoselectivity and also promises to be efficient for the late-stage functionalization of skeletons of drugs and natural products. Mechanism studies indicate that the reaction involves the in situ generated α,β-unsaturated ketones
Synthesis of Highly Substituted Pyridines through Copper-Catalyzed Condensation of Oximes and α,β-Unsaturated Imines
作者:Wei Wen Tan、Yew Jin Ong、Naohiko Yoshikai
DOI:10.1002/anie.201704378
日期:2017.7.3
A copper-catalyzed condensation reaction of oxime acetates and α,β-unsaturated ketimines to give pyridine derivatives is reported. The reaction features mild conditions, high functional-group compatibility, and high regioselectivity with respect to unsymmetrical oxime acetates, thus allowing the preparation of a wide range of polysubstituted pyridines, many of which are not readily accessible by conventional
Asymmetric Hydrogenation of C=N Double Bond with Modified Raney Nickel 1. New Determination Method for the Reaction Mechanism Using Asymmetric Catalyst
The hydrogenation process of ethyl 2-acetoximinopropionate was investigated by means of a novel technique using asymmetric hydrogenation with an asymmetrically modified R–Ni catalyst. It was found that the hydrogenation of ethyl 2-acetoximinopropionate to ethyl alaninate proceeded in two steps through ethyl acetoxyalaninate, and that the asymmetric hydrogenation was performed in the step of the formation
A Cu-catalyzed protocol has been developed for the rapid construction of a wide spectrum of structurally interesting spiropyrroline skeletons. This method utilizes readily accessible ketoximes and alkenes as the starting materials and exhibits broad substrate scope and good functional group compatibility. Furthermore, the reaction can be applied for the late stage modification of bioactive pregnenolone derivatives. The mechanistic investigation suggests that the reactions proceed through a radical process.