@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 {7302,
	title = {ORGANOMETALLIC OXO CHEMISTRY .4. REACTIVITY OF CP-ASTERISK-W(O)2(CH2SIME3) TOWARD PARA-TOLYL ISOCYANATE - CYCLOADDITION REACTIONS OF TUNGSTEN-OXO AND TUNGSTEN-IMIDO LINKAGES},
	journal = {Organometallics},
	volume = {11},
	number = {9},
	year = {1992},
	note = {ISI Document Delivery No.: JN066Times Cited: 50Cited Reference Count: 40},
	month = {Sep},
	pages = {3104-3110},
	type = {Article},
	abstract = {{Treatment of CP*W(O)2(CH2SiMe3) with p-tolyl isocyanate under appropriate experimental conditions leads to the formation of Cp*W(O)(NC6H4-p-Me)(CH2SiMe3) (1), Cp*W(NC6H4-p-Me)2(CH2SiMe3) (2), or Cp*W(NC6H4-P-Me)[N(C6H4-P-Me)C(O)N(C6H4-P-Me)](CH2SiMe3) (3). Each of the complexes 1-3 is derived in a sequential manner from its precursor by incorporation of an additional p-tolyl isocyanate fragment or molecule. The spectroscopic properties of these organometallic imido complexes are consistent with their possessing three-legged (1 and 2) and four-legged (3) piano-stool molecular structures. These conclusions have been confirmed by single-crystal X-ray crystallographic analyses of 2 and 3. Crystal data for 2: triclinic},
	keywords = {ACTIVATION, AMIDO, AMMOXIDATION, COMPLEXES, LIGANDS, METAL, MOLYBDENUM, OXIDATION, propylene, SULFIDO},
	isbn = {0276-7333},
	url = {<Go to ISI>://A1992JN06600027},
	author = {Legzdins,Peter and Phillips, E. C. and Rettig, S. J. and Trotter, J. and Veltheer, J. E. and Yee, V. C.}
}
@article {7302,
	title = {ORGANOMETALLIC OXO CHEMISTRY .4. REACTIVITY OF CP-ASTERISK-W(O)2(CH2SIME3) TOWARD PARA-TOLYL ISOCYANATE - CYCLOADDITION REACTIONS OF TUNGSTEN-OXO AND TUNGSTEN-IMIDO LINKAGES},
	journal = {Organometallics},
	volume = {11},
	number = {9},
	year = {1992},
	note = {ISI Document Delivery No.: JN066Times Cited: 50Cited Reference Count: 40},
	month = {Sep},
	pages = {3104-3110},
	type = {Article},
	abstract = {{Treatment of CP*W(O)2(CH2SiMe3) with p-tolyl isocyanate under appropriate experimental conditions leads to the formation of Cp*W(O)(NC6H4-p-Me)(CH2SiMe3) (1), Cp*W(NC6H4-p-Me)2(CH2SiMe3) (2), or Cp*W(NC6H4-P-Me)[N(C6H4-P-Me)C(O)N(C6H4-P-Me)](CH2SiMe3) (3). Each of the complexes 1-3 is derived in a sequential manner from its precursor by incorporation of an additional p-tolyl isocyanate fragment or molecule. The spectroscopic properties of these organometallic imido complexes are consistent with their possessing three-legged (1 and 2) and four-legged (3) piano-stool molecular structures. These conclusions have been confirmed by single-crystal X-ray crystallographic analyses of 2 and 3. Crystal data for 2: triclinic},
	keywords = {ACTIVATION, AMIDO, AMMOXIDATION, COMPLEXES, LIGANDS, METAL, MOLYBDENUM, OXIDATION, propylene, SULFIDO},
	isbn = {0276-7333},
	url = {<Go to ISI>://A1992JN06600027},
	author = {Legzdins,Peter and Phillips, E. C. and Rettig, S. J. and Trotter, J. and Veltheer, J. E. and Yee, V. C.}
}
