Direct asymmetric additions of ArTi(O-i-Pr)(3) to aldehydes catalyzed by a titanium catalyst of (R)-H(8)-BINOL are reported. The reactions proceed instantaneously at room temperature, affording alcohols in ≥90% ee. Importantly, the ArTi(O-i-Pr)(3) reagent differentiates the ligand effectiveness in an order of H(8)-BINOL > BINOL > TADDOL > diol 3 > disulfonamide 2.
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