Hydrido-bridged

The 2-butyl cation is the smallest secondary cation that can be stabilized either by C-C or C-H hyperconjugation. Experimental results give evidence for two equilibrating isomers.33 MP2/6-311G(d,p) calculations show that the symmetrically hydrido-bridged structure 11 is marginally more stable than the partially methyl-bridged structure 10.34 35... 

X-Ray/Neutron Diffraction Data for Hydrido-Bridged Complexes... 

PMePh)3]. A mixed hydrido/hydrogensulfido bridge between two rheniums is known [Re2Br4(/x-H) (yu-SH)(/u-dppm)2], and a rare jy -coordination of a fullerene has been found in the hydrido-bridged dirhenium complex [Re2H8(PMe3)4(r/, r/ -Ceo)]- ... 

McMurry has reported an unusually stable j,-hydrido-bridged cation, the [4.4.4]tetradecyl cation (135). Most of the other such carbocations are highly unstable and could be characterized at very low temperatures, typically around... 

Although the acyclic p-hydrido-bridged carbomonocations (e.g., 137) cannot be prepared, Sorensen has shown that the acyclic p-hydrido-bridged carbodications can be readily prepared. The following such carbodications have been prepared from their corresponding diols in FSO3H/SO2CIF 2,6-dimethyl-4-isobutylheptane-2,6-diyl dication (139), 4,6-trimethyl-4-isobutylheptane-2,6-diyl dication (140), and 4,4-diisobutyl-2,6-dimethylheptane-2,6-diyl dication (141). 

While admitting that a full molecular orbital treatment may be necessary to describe accurately the bonding in these species, our simple arguments above provide (at least) an accurate prediction of trends in hydrido-bridged metal-metal distances. 

A New Class of Hydrido-Bridged Platinum Complex with Application in Catalysis... 

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