Table 2.

Scope of the Enantioselective α-Benzylation of Aldehydes with Alcohols^a

^aAlcohol (0.5 mmol), aldehyde (2.0 equiv), lutidine (50 mol %), water (30 equiv), organocatalyst 8 (20 mol %), and photocatalyst 18 (0.5 mol %) were irradiated in DMA with a 34 W blue LED lamp at 0 °C. Isolated yields are reported. Enantioselectivities were determined by chiral HPLC analysis following reduction of the crude aldehydes to the corresponding alcohols.

^bCharacterized as the corresponding alcohol.

^cAldehyde (5.0 equiv).

^dYield determined by ¹H NMR.

^eFrom the Z-starting material, 25 was obtained as a 4.5:1 mixture of Z and E isomers; chiral HPLC analysis was performed following reduction of the crude aldehyde to the corresponding alcohol and subsequent hydrogenation of the alkene.