Abstract
The tremendous advances in N-Heterocyclic carbenes (NHCs) have made them the ligand of choice for many transition-metalcatalyzed transformations. Due to the stability of the transition metal complexes of NHCs as well as their stability to air and moisture, NHCs are regarded as an attractive alternative to their phosphine counterparts. To date, research has largely focused on five-membered ring carbenes. However, several reports have demonstrated that changes to the size of the heterocyclic ring (six-, seven-, and eightmembered derivatives) can affect the properties including increased basicity, greater steric demand, and larger N-CNHC-N angle. In this review, we survey recent developments in the design and synthesis of some expanded ring NHCs with a particularly strong influence on the metal’s coordination.
Keywords: N-Heterocyclic carbenes, Rhodium, Iridium, Expanded ring NHCs, Catalysis, Ligand.
Call for Papers in Thematic Issues
Catalytic C-H bond activation as a tool for functionalization of heterocycles
The major topic is the functionalization of heterocycles through catalyzed C-H bond activation. The strategies based on C-H activation not only provide straightforward formation of C-C or C-X bonds but, more importantly, allow for the avoidance of pre-functionalization of one or two of the cross-coupling partners. The beneficial impact of ...read more
Related Books
Advances in Organic Synthesis
The Synthetic Methods, Structures, and Properties of the Ca-C σ Bond Organocalcium Containing Compounds
Advances in Organic Synthesis
Chemistry of Bipyrazoles: Synthesis and Applications
Advances in Organic Synthesis
Advanced Nanocatalysis for Organic Synthesis and Electroanalysis
Advances in Organic Synthesis
Advances in Organic Synthesis
9