A novel axially dissymmetric ligand with chiral 2,2,2-trifluoro-1-hydroxyethyl groups

Novel axially dissymmetric ligands (1) with two more chiral carbons were synthesized through homo-coupling of o-bromo-(R or S)-(2,2,2-trifluoro-1-acetoxyethyl)benzene. A high asymmetric induction was accomplished using 5 mol% of the Ti complex of this ligand for the reaction of benzaldehyde with Et2Zn giving 85% ee of 1-phenylpropanol in 97% isolation yield.