Copper-catalyzed asymmetric propargylic substitution with salicylaldehyde-derived imine esters
Ruo-Qing Wang1,2, Chong Shen1, Xiang Cheng1
1Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, College of Chemistry and Molecular Sciences, Suzhou Institute of Wuhan University, Wuhan University, Wuhan, Hubei, 430072, P. R. China. cjwang@whu.edu.cn.
Abstract:
Copper-catalyzed asymmetric propargylic substitution with salicylaldehyde-derived imine esters and propargylic carbonates has been successfully realized, generating a wide range of chiral amino acid derivatives containing propargylic groups with excellent results (up to 95% yield and 94% ee). The ortho-hydroxy group of the salicylaldehyde-derived imine esters is crucial to increase the reactivity and stabilize the azomethine ylide, which may be due to the formation of an intramolecular hydrogen bond between the hydroxyl group and the imine group. A series of synthetic transformations were carried out to access other important chiral compounds, which displayed the synthetic versatility.
More Related Videos
06:31Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators
Published on: November 27, 2015
08:12A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Related Concept Videos
Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction
Acid Halides to Esters: Alcoholysis
Alkylation of β-Diester Enolates: Malonic Ester Synthesis
Preparation of Alcohols via Substitution Reactions
Alcohols can be synthesized from alkyl halides via nucleophilic substitution reactions. The highly polar carbon-halogen bond in the substrate makes halide a good leaving group. The hydroxide ion or water can act as a nucleophile to take the place of halide and form an alcohol. The substitution reactions occur via two different reaction pathways, SN1 or SN2, depending on the nature of carbon attached to the halide.
Primary alcohols are synthesized from primary alkyl halides, and the...
α-Hydroxy Ketones via Reductive Coupling of Esters: Acyloin Condensation Overview
Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo,...
