CHELATE-CONTROLLED DIASTEREOSELECTIVE HYDROGENATION WITH HETEROGENEOUS CATALYST

摘要

A catalyst, method of using, and use of a hydrogenation catalyst, preferably palladium on a support, preferably alumina or activated charcoal support. This in the presence of lithium salts, with salts such as the borates being preferred. This provides hydrogenation of precursors to give rise to a stereoselective, such as diastereoselective bias in the product of alkene hydrogenation using the catalyst.;This equation, using the preferred substrate, best illustrates the invention:;

主权项

1. A method of stereoselective, hydrogenation, the method comprising providing a substrate of formula: wherein Cycl represents an unsaturated moiety being a five or six membered heterocyclic ring and the heteroatom is selected from the group consisting of O, S, N and P; and R1 is selected from a group consisting of H, CH3, C1 to C6 alkyl chain, and C1 to C6 alkyl chain substituted with heteroatom selected from O, S, N, and; reacting the substrate with hydrogen under pressure in the presence of a catalyst composition, the catalysts composition comprising: a metal hydrogenation catalyst on a support in the presence of a lithium salt.