Tethered single-site catalysts

Table 16.1 Homogeneous catalysts, tethered single-site catalysts, and biphase catalysts for the hydrogenation of aromatic hydrocarbons.

A fist of the metal complexes that have been claimed to generate catalysts for the hydrogenation of carbocyclic aromatic rings is provided in Table 16.1. This list includes homogeneous catalysts, biphase catalysts, and tethered single-site catalysts. 

One area which continues to attract interest is increasing the activity of single-site catalysts when supported, making up some of the deficit from which they suffer compared to their solution-soluble cousins. In this vein, Collins recently described in broad terms the synthesis of and polymerization using tethered ansa-metallocenes, the activity of which is comparable to a homogeneous analogue we await full details of catalyst structures and methods of preparation. ... 

One of the very first attempts to hydrogenate aromatic compounds by means of a single-site metal catalyst was reported by Fish and coworkers, who were able to tether RhCl(PPh3)2 moieties to a cross-linked phosphinated styrene/divinylbenzene (DVB) resin (RhCl(PPh3)2/P) (Fig. 16.3). 

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