STEREOSELECTIVE EFFECTS IN THE SOLID-PHASE HYDROGENATION OF UNSATURATED L-HYDROXYPROLINE DERIVATIVES

The solid-phase catalytic hydrogenation of (R)-4-tert-butoxy-Delta(1)- pyrroline-2-carboxylic acid under the action of hydrogen spillover was studied. The reaction proceeds stereoselectively with the predominant formation of the L-amino acid. The configuration of the asymmetric ce nter formed is determined by that of the asymmetric C(4) atom. The maj or portion of the isotope label is incorporated into the allylic C(3) and C(5) positions, and the beta-H atoms are more mobile. Using quantu m-chemical calculations, the geometric structure of the L-hydroxyproli ne molecule was calculated, and the spin-spin coupling constants for t his tritium-labeled amino acid were determined.