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New types of chiral phosphorus/nitrogen ligands, capable of forming six-membered-ring metal chelates have been prepared from α,α,α′,α′-tetraaryl-1,2-dioxolane-4,5-dimethanols (TADDOLs), PCl3, and dihydrooxazole alcohols (from amino acids) (7 in Scheme 1). The X-ray crystal structure of a Rh complex of one of these ligands, 8b, has been determined (Scheme 2 and Fig.). Enantioselective hydrosilylations of dialkyl and aryl alkyl ketones with Ph2SiH2/0.01 equiv. RhI⋅7 have been studied and found to provide secondary alcohols in enantiomer ratios of up to 97 : 3 (Scheme 3 and Table). The ligand prepared from (R,R)-TADDOL and the (R)-valine-derived (R)-α,α-dimethyl-4-isopropyl-4,5-dihydrooxazole-2-methanol gives better results than the (R,R,S)-isomer (7dvs.7c in Scheme 3), and an i-Pr group on the 4,5-dihydrooxazole ring gives rise to a slightly better selectivity than a Ph group. With the (R,R,R)-ligands the hydrogen transfer occurs from the Re face of the oxo groups (Scheme 4).