Ruthenium(II)-Catalyzed Grignard-Type Nucleophilic Addition of C(sp 2 )-H Bonds to Unactivated Aldehydes.

The Grignard-type nucleophilic addition of C(sp 2 )-H bonds to aldehydes catalyzed by high-oxidation-state transition metal complexes is limited to activated aldehydes. Herein, we report the first example of Grignard-type nucleophilic addition of C(sp 2 )-H bonds to unactivated aldehydes catalyzed by high-oxidation-state ruthenium(II). The reaction has mild reaction conditions and good functional group tolerance. The corresponding alcohol products are obtained in good to excellent yields.