Oxidation states tungsten-alkyne complexes

Another class of transition metal complexes studied by our group consists of alkyne and vinylidene complexes of tungsten and molybdenum in high oxidation states. Alkyne complexes are interesting from a theoretical point of view because they may be considered to be either side-on coordinated ligand complexes or metallacyclopropenes. They are also important as possible intermediates in the cyclooligomerization and polymerization of alkynes. o " Scheme 3 shows the two types of alkyne complex that were studied. 

R. Stegmann, A. Neuhaus, and G. Frenking,/. Am. Chem. Soc., 115,11930 (1993). Theoretical Studies of Organometallic Compounds. V. Alkyne and Vinylidene Complexes of Molybdenum and Tungsten in High Oxidation States. 

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