Diaminocarbene model ligand

One of the first mechanistic computational studies on NHC-TM chemistry was published in 1998 by Rosch on the Heck reaction.This study employed a simple diaminocarbene (DAC) model ligand and characterised the alkene insertion and p-H elimination steps of the cationic pathway, derived from a cis-[(DAC)2PdBr(Ph)] intermediate via Br /C2H4 substitution. The neutral pathway via initial DAC/C2H4 substitution) was discounted on the basis of the non-observation of free NHC experimentally and the fact that cleavage of the NHC Pd bond would be prohibitively high in energy. A mixed... 

This Chapter is devoted to the development of cobalt-, rhodium- and iridium-based catalysts that contain N-heterocyclic carbene (NHC) ligands. It will cover their most relevant catalytic applications, along with stoichiometric model reactions, except for catalytic oxidations and reductions such as hydrogenations, hydrosilylations and hydroborations, which are treated in detail in Chapters 12 and 13. Since the NHC chemistry of Group 9 metals is one of the most developed areas in this field, this overview will only cover the chemistry of classical NHCs, namely cyclic diaminocarbenes. Chapter 5 reviews the chemistry of the non-classical NHCs, to which the reader is referred. Finally, this Chapter does not pretend to be exhaustive and further details may be found in previous overviews. ... 

---

See also in sourсe #XX -- [ ]

---