TUngsten complexes four-electron alkyne ligands

Four-Electron Alkyne Ligands in Molybdenum(ll) and Tungsten(ll) Complexes... 

As stated in the Introduction, Templeton7 published a comprehensive review entitled Four Electron Alkyne Ligands in Molybdenum(II) and Tungsten(II) Complexes, including halocarbonyl complexes, which dealt with the literature up to 1987. Hence, this section of the review deals with the literature on halocarbonyl alkyne and alkene complexes published from 1987 to mid-1995. The vast majority of papers that have appeared during this period are concerned with the reactions of [MI2(CO)3(NCMe)2] (M = Mo, W) and their derivatives with alkynes, which begin this section of the review. 

J.L. Templeton - Four-Electron Alkyne Ligands in Molybdenum (II) and Tungsten (II) Complexes, Adv. Organomet. Chem. 29, 1,1989. 

Ward BC, Templeton JL (1980) Nuclear magnetic resonance studies of alkynes as four-electron donor ligands in monomeric tungsten(n) complexes. J Am Chem Soc 102 1532-1538... 

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