Enantioface-Selective Coordination of Prochiral 1,3-Dienes to Planar-Chiral Cyclopentadienyl-Ruthenium Complexes
摘要:
The treatment of planar-chiral (eta(5):eta(1) cyclopentadienylphosphine)bis(acetonitrile)ruthenium complexes 1 with prochiral dienes led to the ligand-exchange reaction that gave (eta(5):eta(1)- cyclopentadienylphosphine)(eta(4)-diene)ruthenium complexes 4-6 and 8-11 with high enantio-face selectivity (up to > 99% de). The configuration of the (eta(4)-diene)ruthenium complexes was determined by crystallographic study of (eta(4)-isoprene)ruthenium complex 6b-I and spectral analyses, including NOE measurements. The selectivity of the reaction is under thermodynamic control of the resulting eta(4)-diene complexes and is affected by the substituents on both the cyclopentadienyl ligand and the diene.