Reactivity of the dinuclear fulvalene cyclopentadienyl zirconium cationic species [{Zr(eta(5)-C5H5)}(2)(mu-CH2)(mu-Cl)(mu-eta(5)-C5H4-eta(5)-C5H4)](+) with isocyanides and carbon monoxide: insertion reactions, spectroscopic characterization and synthetic aspects

The dinuclear cationic zirconium compound [{Zr(eta (5)-C5H5)}(2)(mu -CH2)(m u -Cl)(mu-eta 5-C5H4-eta (5)-C5H4)][BMe(C6F5)(3)] 1 reacts in dichlorometha ne at - 78 degreesC with three equivalents of RNC (R = 'Bu, 2,6-Me2C6H3) vi a insertion into the Zr-mu -methylene bond to give the new zirconium cation ic species [{Zr(eta (5)-C5H5)}(2)(Cl)(CN'Bu) {mu-[eta (2)-CN('Bu)-CH2-eta ( 2)-CN('Bu}(mu-eta (5)-CH4-eta5-C5H4)]-[BMe(C6F5)(3)] 2 and [{Zr(eta (5)-C5H 5)}(2)(Cl){CN(2,6-Me2C6H3)}[mu-eta (2){CN(2,6-Me2C6H3)}-CH2-eta (2)-{CN(2,6 -Me2C6H3)}](mu-eta (5)-C5H4-eta (5)-C5H4)][BMe(C6F5)(3)] 3, whereas reactio n with CO affords the ketene compound [{Zr(eta (5)-C5H5)}(2)(mu -Cl){mu -OC (=CH2)}(mu-eta (5)-C5H4-eta (5)-C5H4][BMe(C6F5)(3)] 4. The new complexes re ported herein were characterized by elemental analysis and IR and NMR spect roscopy. (C) 2001 Published by Elsevier Science B.V.