Intermediates for the synthesis of bisphosphine compounds

摘要

The invention relates to novel bisphosphonates and to processes for their preparation and for their resolution into the enantiomers. The bisphosphonates according to the invention are valuable intermediates for the preparation of bisphosphine compounds, especially chiral bisphosphine ligands. These in turn are constituents of transition metal complexes which are used as catalysts inter alia in asymmetric hydrogenation. The novel bisphosphonates have the general formula (I) <IMAGE> (I) in which R1 is linear or branched alkyl having up to 6 carbon atoms, aryl or aralkyl, each of which can optionally be substituted, or two radicals R1 together are a bridging hydrocarbon radical having up to 6 carbon atoms, and can exist in the form of their racemates or as enantiomers.