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The preparation and use of chiral (salen)titanium complexes to induce the asymmetric addition of trimethylsilyl cyanide to aldehydes are reported. dimeric salen(titanium) complexes, where the titanium atoms are linked by two oxygen atoms and the optimum catalyst possesses tert-butyl substituents in the 3- and 5-positions of the aromatic rings, are found to be a novel class of catalysts for the reaction. High levels of asymmetric induction are obtained using the optimum catalyst and aromatic aldehydes, with the product cyanohydrin trimethylsilyl ethers obtained between 76% and 92% enantiomeric excess at ambient temperature.

An experiment was conducted showing the hydrogenation of chiral 2,2'-functionalized 1,1'-binapthyls with Pd and Ru solid-supported metal catalysts which were clean and gave a convenient pathway to 5,5',6,6',7,7',8,8'-octahydro-1,1'-dinapthyl derivatives. It was observed that, in most cases, no racemization was present in the course of the reaction. . .