@article {2088,
	title = {Reactivity of Cp*Mo(NO)(= CHCMe3) with olefins and dienes: C-H activation reactions of molybdenacyclobutanes},
	journal = {Organometallics},
	volume = {27},
	number = {12},
	year = {2008},
	note = {ISI Document Delivery No.: 312BHTimes Cited: 5Cited Reference Count: 30Graham, Peter A. Buschhaus, Miriam S. A. Pamplin, Craig B. Legzdins, Peter},
	month = {Jun},
	pages = {2840-2851},
	type = {Article},
	abstract = {Reactions of a variety of cyclic and acyclic olefins with the title alkylidene complex (formed spontaneously by loss of neopentane from Cp*Mo(NO)(CH2CMe3)(2) under ambient conditions) result in the initial formation of molybdenacyclobutane complexes (Cp* = C5Me5). These molybdenacyclobutane complexes do not react via olefin metathesis or cyclopropanation pathways, but instead via C-H activation. Thus, when cyclopentene is the olefinic substrate, the direct result of C-H activation at the beta-position of the metallacyclobutane affords a thermally stable allyl hydrido complex that can be isolated. Such an allyl hydride intermediate is not isolable for larger cyclic olefins (cyclohexene, cycloheptene, and cyclooctene) or acyclic olefins (allylbenzene and 1-hexene). Instead, those complexes react further, undergoing a second C-H activation at the allylic position to produce eta(4)-trans-diene complexes concomitant with the loss of dihydrogen. Upon heating, these eta(4)-trans-diene complexes liberate diene, thereby enabling the 14e Cp*Mo(NO) metal fragment to catalyze the oligomerization of cyclic olefins and dienes including cyclohexene and 1,4-cyclohexadiene. In the case of the acyclic olefin allylbenzene, the metal fragment catalyzes a dimerization to (E)-(4-methylpent-1-ene-1,5-diyl)dibenzene under ambient conditions.},
	keywords = {ALPHA-HYDROGEN ABSTRACTION, BONDS, COMPLEXES, CRYSTAL-STRUCTURES, CYCLOHEXENE, METATHESIS, MOLYBDENUM, NEOPENTYLIDENE, OLIGOMERIZATION, TUNGSTEN},
	isbn = {0276-7333},
	url = {<Go to ISI>://000256643600023},
	author = {Graham, P. A. and Buschhaus, M. S. A. and Pamplin, C. B. and Legzdins,Peter}
}
@article {2027,
	title = {Transformations of cyclic olefins mediated by tungsten nitrosyl complexes},
	journal = {Organometallics},
	volume = {27},
	number = {18},
	year = {2008},
	note = {ISI Document Delivery No.: 348URTimes Cited: 3Cited Reference Count: 35Buschhaus, Miriam S. A. Pamplin, Craig B. Blackmore, Ian J. Legzdins, Peter},
	month = {Sep},
	pages = {4724-4738},
	type = {Article},
	abstract = {This report describes investigations that have elucidated the nature, extent, and mechanism of the cyclic-olefin oligomerization effected by a series of tungsten precatalysts, with particular focus on Cp*W(NO)(CH2CMe3)(2) (1) and Cp*W(NO)(CH2SiMe3)(eta(2)-CPhCH2) (2). Upon thermolysis, these precatalysts oligomerize simple cyclic olefins, from cyclopentene to cyclooctene, into ring-retaining oligomers as high as dodecamers (depending on the substrate) with remaining sites of unsaturation. Precatalyst initiation involves the coupling of one equivalent of the substrate with the reactive 16e intermediate thermally generated by the precatalyst (i.e., an alkylidene by 1 or an eta(2)-alkyne complex by 2), followed by rearrangement of the coupled ligand in the metal{\textquoteright}s coordination sphere either to an olefin or to a diene (with concomitant loss of two hydrogen atoms). The rearranged ligand is displaced from the metal center as two equivalents of substrate coordinate to form a putative bis-olefin complex, Cp*W(NO)(cyclic olefin)2, that represents the convergent entry point to the catalytic cycle for the precatalysts. The coordinated olefins undergo metal-mediated coupling to form a metallacyclopentane complex. The metallacycle then undergoes beta-hydrogen activation and reductive elimination to generate an eta(2)-cyclic-olefin dimer. Further incorporation of substrate leads to formation of trimers and higher oligomers. Alternatively, expulsion of any coordinated oligomer from the tungsten center regenerates the reactive bis-olefin complex. Finally, decomposition of the tungsten catalyst species is consistent with a bimetallic pathway. All new organometallic complexes have been characterized by conventional spectroscopic and analytical methods, and the solid-state molecular structures of several compounds have been established by X-ray crystallographic analyses.},
	keywords = {1, 3-CYCLOHEXADIENE, ALKYLIDENE COMPLEXES, C-H ACTIVATION, CATALYTIC-ACTIVITY, CRYSTAL-STRUCTURES, CYCLOHEXENE, METATHESIS, MOLYBDENACYCLOBUTANES, MOLYBDENUM, REACTIVITY},
	isbn = {0276-7333},
	url = {<Go to ISI>://000259236100022},
	author = {Buschhaus, M. S. A. and Pamplin, C. B. and Blackmore, I. J. and Legzdins,Peter}
}
