Tantalum, organometallic

Monomeric, paramagnetic chlorohydrides snch as MH2CI2 (PR3)4 derive from facile oxidative addition of H2 to MCl2(PR3)4 complexes. Of these 17e dodecahedral complexes, (32) is the most interesting (eqnation 17). Its thermolysis in solution offers a qnadruply bridged hydride (33) and it can also be rednced to a monomeric Ta 16e species (34). Ta hydrides display a hydridic character (see Hydride Complexes of the Transition Metals), as shown by the reduction of CO by cyclopentadienyl derivatives. (see Niobium Tantalum Organometallic Chemistry)... 

Metal-mediated Protein Modification Niobium Tantalum Organometallic Chemistry Polynuclear OrganometaUic Cluster Complexes. 

Based in part on the article Niobiiun Tantalum Organometallic Chemistry by David E. Wigley which appeared in the Encyclopedia of Inorganic Chemistry, First Edition. 

Carbonyl Complexes of the Transition Metals Mechanisms of Reaction of Organometallic Complexes Niobium Tantalum Organometallic Chemistry. 

Calix[4]arenes have been used as a preorganized set of 0-donor atoms. Monomeric or dimeric species were obtained depending on the calixarene substituents. They were used to develop the organometallic chemistry of Nb and Ta in various oxidation states, the electron reservoir of the Nb=Nb bond is able to activate small molecules including N2 see Niobium Tantalum Organometallic Chemistif). 

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