The molecular structures, chemical bonding and magnetochemistry of the three-coordinate iron(II) NHC complexes [(NHC)Fe{N(SiMe(3))(2)}(2)] (NHC = IPr, 2; NHC = IMes, 3) are reported.

The reaction of (μ-Cl)2Ni2(NHC)2 (NHC = 1,3-bis(2,6-diisopropylphenyl)-1,3-dihydro-2H-imidazol-2-ylidene (IPr) or 1,3-bis(2,6-diisopropylphenyl)imidazolidin-2-ylidene (SIPr)) with either one equivalent of sodium cyclopentadienyl (NaCp) or lithium indenyl (LiInd) results in the formation of diamagnetic NHC supported Ni(I) dimers of the form (μ-Cp)(μ-Cl)Ni2(NHC)2 (NHC = IPr (1 a) or SIPr (1 b); C...

The reactivity of the N-heterocyclic carbene (NHC) 1,3-bis(2,6-diisopropylphenyl)imidazol-2ylidene towards dichlorosilane H2SiCl2, bis(trifluoromethanesulfonato)silane H2Si(OTf)2 (OTf = OSO2CF3), and silyl trifluoromethanesulfonate H3SiOTf has been investigated. It turned out that the coordination of the NHC ligand can occur stepwise to form the three neutral compounds (NHC)SiH2Cl2 (1), (NHC)2S...

In the last twenty years, N-heterocyclic carbenes (NHCs) have acquired considerable popularity as ligands for transition metals, organocatalysts and in metal-free polymer synthesis. NHCs are generally derived from azolium based salts NHCH+X− by deprotonation or reduction (chemical or electrochemical) of NHCH+. The extensive knowledge of the physicochemical properties of NHCH+/NHC system could h...

NHC-stabilized 2-hydrophosphasilenes are obtained from 1,2-dihydro-2-chlorophosphasilanes as Si(iv) precursors by a NHC-assisted 1,2-elimination of HCl. The NHC-exchange of these compounds is demonstrated as a proof of donor acceptor bonding between NHC and the silicon centre of the "Si[double bond, length as m-dash]P" moiety. We have also explored the possibility of similar exchanges in NHC-st...

The mesomeric betaine imidazolium-1-ylphenolate forms a borane adduct with tris(pentafluorophenyl)borane by coordination with the phenolate oxygen, whereas its NHC tautomer 1-(2-phenol)imidazol-2-ylidene reacts with (triphenylphosphine)gold(I) chloride to give the cationic NHC complex [Au(NHC)2][Cl] by coordination with the carbene carbon atom. The anionic N-heterocyclic carbene 1-(2-phenolate)...

Quantum chemical calculations of the compound B2(NHC )2 and a thorough examination of the electronic structure with an energy decomposition analysis provide strong evidence for the appearance of boron–boron triple bond character. This holds for the model compound and for the isolated diboryne B2(NHC )2 of Braunschweig which has an even slightly shorter B–B bond. The bonding situation in the mol...

CsBr3 was investigated as a new and convenient oxidant for NHC-Au(I) complexes (NHC = imidazo[1,5-a]pyridin-3-ylidene) for the preparation of the respective Au(III) complexes. The Au(I) complexes were synthesized by the silver salt method using [(NHC)2Ag]PF6 and (tht)AuBr. Unexpectedly, the reactions yielded both neutral (NHC)AuBr and ionic [(NHC)2Au]PF6, depending on the N-substituent of the N...