Probing Supported Metal Catalysts by NMR without Utilizing High-Resolution Techniques

Probing Supported Metal Catalysts by NMR without Utilizing High-Resolution Techniques 

The H NMR spectrum of the Si02-supported complex designated 1 Si —O—Rh(aliyl)2, has just one signal at 8 = 1.2 ppm from TMS (see Curve A in Fig. 73). This arises from the protons of the ally ligands bound to Rh. The width (FWHM = 1.7 ppm) of the resonance suggests that all the ally protons experience essentially the same average environment, and corroborates the view that all the Rh nuclei in the surface allyl complexes are present in discrete molecular entities. 

Bond Lengths, Structure, and Mechanism in Heterogeneous Catalysis and in Chemisorbed States 

This work constitutes a significant achievement if only because it illustrates how the nature of hydrocarbon groupings can be deduced de novo, for states of chemisorption much more nearly like those involved in practical heterogeneous catalysis. 

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