Asymmetric Alkynylation Reactions of Aldehydes Using a Zn(OTf)2-Chiral Ligand-Base System

Abstract

Optically active propargylic alcohols serve as an important building block in asymmetric synthesis. The customised synthesis of chiral ligands and transition metal activators as catalysts, to effect asymmetric alkynylation reactions, continue to feature in the literature. This review article focuses upon the use of Zn(OTf) 2 , in conjunction with 2-point chiral ligands, for effecting asymmetric alkynylation reactions to aldehydes.

Cheap and Long‐Life Reusable Polymer for Asymmetric Organozinc Catalysis Based on Camphor‐Derived Hydroxyamides

“…Chiral organometallic catalysts based on zinc have found broad application in asymmetric organic synthesis . In some cases, these catalysts could be efficiently recycled from the reaction media and reused several times in new reactions .…”

“…One of the most studied asymmetric reactions promoted by organozinc catalysts is the enantioselective addition of organometallic reagents (mainly organozinc ones) to aldehydes . In this line, many recyclable catalysts based in the immobilization of the most successful homogeneous ligands (i.e., β‐amino alcohols) have been described for this valuable asymmetric C―C bond‐forming reaction .…”

Asymmetric Direct Alkynylation Catalyzed by Chiral Ru−Bis(oxazolinyl)phenyl Complexes

“…Asymmetric alkynylation with terminal alkynes can provide optically active propargylic alcohols that are useful for materials science or pharmaceutical chemistry. − Recently, catalytic direct asymmetric alkynylation with chiral Zn, In, and Cu catalysts was developed by Carreira et al, Shibasaki et al, and Sawamura et al, respectively. Here we report a new ruthenium-catalyzed alkynylation reaction by use of chiral Ru−phebox complexes (Figure ).…”