Grignard allylic substitution reaction catalyzed by 1,2,3-triazol-5-ylidene magnesium complexes

Chemistry of Compounds Based on 1,2,3-Triazolylidene-Type Mesoionic Carbenes

Mesoionic carbenes (MICs) of the 1,2,3-triazolylidene type have established themselves as a popular class of compounds over the past decade. Primary reasons for this popularity are their modular synthesis and their strong donor properties. While such MICs have mostly been used in combination with transition metals, the past few years have also seen their utility together with main group elements. In this paper, we present an overview of the recent developments on this class of compounds that include, among others, (i) cationic and anionic MIC ligands, (ii) the donor/acceptor properties of these ligands with a focus on the several methods that are known for estimating such donor/acceptor properties, (iii) a detailed overview of 3d metal complexes and main group compounds with these MIC ligands, (iv) results on the redox and photophysical properties of compounds based on MIC ligands, and (v) an overview on electrocatalysis, redox-switchable catalysis, and small-molecule activation to highlight the applications of compounds based on MIC ligands in contemporary chemistry. By discussing several aspects from the synthetic, spectroscopic, and application point of view of these classes of compounds, we highlight the state of the art of compounds containing MICs and present a perspective for future research in this field.

Planar-chiral ferrocene-based triazolylidene copper complexes: synthesis, characterization, and catalysis in asymmetric borylation of α,β-unsaturated ester

1,2,3-Triazol-5-ylidenes have recently attracted considerable attention as versatile ligands because of their strong electron-donating properties and structural diversities. While some efforts have been devoted to the development of chiral triazolylidene-metal complexes, there is no example achieving asymmetric induction by base-metal complexes with triazolylidene ligands. Herein, we synthesized planar-chiral ferrocene-based triazolylidene copper complexes, which enabled the asymmetric borylation of methyl cinnamate with bis(pinacolato)diboron with good enantioselectivity.

Chiral triazolylidene-Pd-PEPPSI: synthesis, characterization, and application in asymmetric Suzuki–Miyaura cross-coupling

A novel triazolylidene-Pd-PEPPSI with ferrocene-based planar chirality has been synthesized, characterized, and applied to the asymmetric Suzuki–Miyaura cross-coupling.

Transition metal-free asymmetric and diastereoselective allylic alkylation using Grignard reagents: construction of vicinal stereogenic centers via kinetic resolution

The first transition metal-free catalyzed diastereoselective and enantioselective asymmetric allylic alkylation (AAA) has been disclosed leading to the construction of vicinal tertiary/quaternary centers via a kinetic resolution protocol starting from readily available starting materials.