Hydrogenation of esters with ru/bidentate ligands complexes.

Abstract

The present invention relates to processes for the redn. by hydrogenation, using mol. H2, of a substrate contg. one or two esters, or lactones, functional groups into the corresponding alc., or diol, said process is carried out in the presence of a base and at least one catalyst or pre-catalyst in the form of a ruthenium complex, [Ru(PP)(NN)S2-nYn]Y2-n [wherein PP = a C6-60-diphosphine bidentate ligand (coordinated via two phosphine groups); NN = a C3-40-bidentate ligand (coordinated through two amino groups and whereby at least one amine group is a primary amine); S = neutral C1-26-neutral monodentate ligand; Y = H, halogen, BH4, AlH4, OH, C1-6-alkoxy, carboxyl radical; n = 0, 1, 2] comprising at least one substituted α-carbon and one primary amine as one of the coordinating atoms. Thus, PhCO2Me was hydrogenated over [RuCl2{(R)-BINAP}{(S,S)-DPEN}] in THF contg. NaOMe to give 77% PhCH2OH. [on SciFinder(R)]