Journal of Molecular Catalysis A-Chemical, Vol.174, No.1-2, 205-211, 2001
Study on catalytic hydrogenation in synthesis of four-directional amine-terminated dendritic molecules
The syntheses of four-directional dendritic molecules derived from pentaerythritol are described. Amine functionalized molecules were synthesized in a two-step reaction sequence which involved cyanoethylation followed by catalytic hydrogenation of the cyano groups to the amine groups with H-2 and Raney nickel as catalyst. Two generations starting from pentaerythritol were synthesized. The products were characterized mainly by H-1 and C-13 NMR as well as by IR. Yields were high in the syntheses of cyanoalkoxypentaerythritols 1N and 2N as well as in the synthesis of aminoalkoxypentaerythritol 1A, but significantly lower in the case of aminoalkoxypentaerythritol 2A. Factors affecting hydrogenation process as well as separation of side products and purification methods for the products are discussed.