@article {1263,
	title = {Synthesis and reactivity of zirconium and hafnium complexes incorporating chelating diamido-N-heterocyclic-carbene ligands},
	journal = {Journal of Organometallic Chemistry},
	volume = {690},
	number = {24-25},
	year = {2005},
	note = {ISI Document Delivery No.: 994VFTimes Cited: 36Cited Reference Count: 51},
	month = {Dec},
	pages = {5788-5803},
	type = {Article},
	abstract = {Early transition metal complexes employing a diamido N-heterocyclic carbene (NHC) ligand set (denoted [NCN]) render the centrally disposed NHC moiety stable to dissociation. Aminolysis reactions with the mesityl-substituted ligand precursor ((Mes)[NCN]H-2) and M(NMe2)(4) (M = Zr, Hf) provide bis(amido)-NHC-metal complexes that can be further converted to chloro and alkyl derivatives. Activation of (Mes)[NCN]M(CH3)(2) with [Ph3C][B(C6F5)(4)] yields {(Mes)[NCN]MCH3} {B(C6F5)(4)}, which is surprisingly inactive for the polymerization of 1-hexene. The zirconium cation did, however, show moderate ability to catalytically polymerize ethylene. The hafnium dialkyls are thermally stable with the exception of the diethyl complex, (Mes)[NCN]Hf(CH2CH3)(2), which undergoes P-hydrogen transfer and subsequent C-H bond activation with an ortho-methyl substituent on the mesityl group. The hafnium dialkyl complexes also insert carbon monoxide and substituted isocyanides to yield eta(2)-acyls and eta(2)-iminoacyls, respectively. In some circumstances, further C-C bond coupling occurs to yield enediolates and eneamidolate metallocycles. The molecular structures of (Mes)[NCN]Hf(CH2CHMe2)(2), (Mes)[NCN]Hf(eta(2)-(2,6-Me2C6H3NCCH3)(CH3), (Mes)[NCN]Hf(eta(2)-(2,6-Me2C6H3NCCH3)(2), (Mes)[NCN]Hf(OC(CH3)=C(CH3)NXy), and [(Mes)[NCN]Hf(OC(Bu-i)=C(Bu-i)O)](2) are included. (c) 2005 Elsevier B.V. All rights reserved.},
	keywords = {AMIDO, CARBON-MONOXIDE, CHEMISTRY, DONORS, ETA-2-IMINOACYL, hafnium, LIVING POLYMERIZATION, MIGRATORY INSERTION, N-heterocyclic carbene, OLEFIN, POLYMERIZATION, PROPERTIES, SPECTROSCOPIC, STABLE CARBENES, STRUCTURAL-CHARACTERIZATION, tridentate ligand, ZIRCONIUM, ZIRCONOCENE COMPLEXES},
	isbn = {0022-328X},
	url = {<Go to ISI>://000234058600046},
	author = {Spencer, L. P. and Fryzuk,Michael D.}
}
@article {4325,
	title = {Ligand elaboration mediated by a Cp*W(NO) template: Stepwise incorporation of small molecules into a tungsten vinyl fragment},
	journal = {Organometallics},
	volume = {17},
	number = {5},
	year = {1998},
	note = {ISI Document Delivery No.: ZC012Times Cited: 21Cited Reference Count: 81},
	month = {Mar},
	pages = {854-871},
	type = {Article},
	abstract = {{Thermolysis of the alkyl vinyl complex Cp*W(NO)(CH2SiMe3)(CPh=CH2) (1) in the presence of unsaturated, heteroatom-containing compounds such as esters and nitriles quantitatively affords metallacyclic products of reductive coupling. These are trapped as 18e complexes via either intramolecular rearrangement or intermolecular reaction with added trapping reagents. The nature of these metallacycles is consistent with the intermediacy of the acetylene complex Cp*W(NO)(eta(2)-CPh=CH) (A) derived in situ from the reductive elimination of SiMe4 from 1. With esters ROAc (R = Me, Et), reductive coupling and C-O bond cleavage yields the alkoxide-containing oxametallacyclopentadiene complexes Cp*W-(No)(eta(2)-O=C(Me)CH=CPh)(OR) (2},
	keywords = {ACTIVATION, ALKYNE COMPLEXES, BOND-CLEAVAGE, C-H, INSERTION, KETONE COMPLEXES, METAL-COMPLEXES, ORGANIC-SYNTHESIS, ORGANOMETALLIC NITROSYL CHEMISTRY, RAY CRYSTAL-STRUCTURE, SEQUENTIAL, ZIRCONOCENE COMPLEXES},
	isbn = {0276-7333},
	url = {<Go to ISI>://000072530700014},
	author = {Legzdins,Peter and Lumb, S. A. and Young, V. G.}
}
