SUBSTRATE SELECTIVE CATALYSIS BY RHODIUM METALLOHOSTS

A novel supramolecular catalyst functioning according to the principles of enzymatic catalysis is described. It consists of a basket-shaped molecule to which a catalytically active Rh(I) complex is attached. The catalyst selectively hydrogenates and isomerizes allyl-substituted dihydroxyarene substrates that are bound in its cavity. The reactivity of this supramolecular catalyst and its affinity for several substrates is compared with that of the corresponding catalyst without a binding site. Features known from enzymatic catalysis, e.g. Michaelis-Menten kinetics and rate enhancement by cooperative binding, are described and discussed.