Tungsten diazene complexes

The overall reaction from 10.25 to 10.26 is an insertion into a metal-hydrogen bond. It is, however, only an apparent insertion, as the Rh — H bond dissociates in the diazene diazenido equilibrium (10-9), as already emphasized by Sutton in 1975. Other interesting cases are the reactions of tungsten mono- and bis-hydrido complexes with diazonium salts. The monohydrido complex 10.27 yields the aryldiazene complex 10.28 (Smith and Hillhouse, 1988) in an 1,1-insertion (10-11). The bishydrido complex 10.29 (10-12), however, adds one of the two H-atoms at the... 

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