The Chemistry of Particular Hydride Complexes

Complex Hydrides with Tertiary Phosphines and Related 

Transition-metal hydride complexes which also contain tertiary phosphines as stabilizing ligands are among the most numerous and stable of presently known hydride complexes. Their relative ease of preparation, and their thermal and oxidative stability, make them suitable materials for carrying out detailed studies of the metal-hydrogen system. As shown in Table III, a considerable range of complexes in this class has been prepared and their infrared and proton magnetic resonance spectra have been studied. The results of these studies are discussed in Section II,B and C, respectively. 

The first known complex in this class, frans-bis(triethylphosphine)-platinum chlorohydride, was prepared by Chatt and co-workers (86). In the light of other hydrides known at that time, in particular the carbonyl hydrides of iron and cobalt and bis(7r-cyclopentadienyl)rhenium hydride, the great stability of this complex was quite unique. It rapidly became clear that tertiary phosphine ligands were markedly effective in stabilizing the metal-hydrogen bond, and ligands such as PhjP, EtjP, o-CaH PlVfe,  

Compound Color M.P. (°C) References to preparation Infrared, h-h (cm 1) NMR chemical shift of M-hydrogen r(p.p.m.) Notes 

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