NEW INSOLUBLE SURFACTANT SYSTEMS AS AIDS IN CATALYSIS - A CONVENIENT METHOD FOR NONBONDED IMMOBILIZATION OF CATALYTICALLY ACTIVE TRANSITION-METAL COMPLEXES

New insoluble surface-active substances are described here for the fir st time. They were synthesized by esterification of the surfactants so dium 11-hydroxy-undecane-1-sulfonate or dodecaethylene glycol monodode cyl ether with an aliphatic amino acyl chloride, reaction of the amino group containing ester with the bifunctional reagent 3-(triethoxysily l) propyl isocyanate, and anchoring the products obtained on silica 10 0 under mild conditions. The surfactants thus immobilized showed a mic ellar effect, as proved by their influence on reaction rate and select ivity in the enantioselective hydrogenation of methyl (Z)-alpha-acetam ido-cinnamate to methyl N-acetyl-phenylalaninate (R) by means of an op tically active rhodium complex in water. The systems were compared wit h an inorganic ion exchanger with dodecyl sulfate counterions and with sodium dodecyl sulfate adsorbed to alumina. The influence of the immo bilized surfactants on reaction rate and selectivity appeared to be de pendent on the mobility of the hydrophobic chains.