Molybdenum complexes pentadienyl

HIGH-VALENT MONO- -PENTAMETHYLCYCLO-PENTADIENYL)VANADIUM AND MOLYBDENUM COMPLEXES... 

The study of organometallic 0x0 complexes has been hindered by the limited number of pure compounds available. One of these complexes, oxobis(f -cyclopentadienyl)molybdenum(IV), CP2M0O, was first reported in 1972 11 jhat preparation involved the reaction of dichlorobis( / -cyclo-pentadienyl)molylxlenum(IV) with aqueous NaOH. Unfortunately, the product obtained by this method is difiicult to purify. The procedure that follows includes a new and reproducible method of purification. A second,... 

ABSTRACT. Dicarbonyl(t 5-cyclopentadienyl)carbyne complexes of molybdenum and tungsten prove to be a valuable synthetic tool Reaction with phosphines provides substituted carbyne complexes and leads via an intramolecular CC-coupling to t 1- or Tj -ketenyl complexes respectively. Electrophiles attack the metal carbyne triple bond forming hetero- and acyclic carbene complexes, r 2-acyl compounds, T -ketene complexes and metalla-dithia-bicyclobutane cations. Dithio-carboxylates are formed in reaction of these dicarbonyl(Ti5 cyclo-pentadienyl)carbyne complexes with sulfur or cyclohexene sulfide. 

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