significantly by the steric effect of bulky groups. However, the influence of steric alkylchain length has not been studied for the diastereoselectivity. In this work, we present a new strategy for the racemic synthesis of β-methyl alcohols to obtain various diastereomer ratios using the Felkin–Anh model. The addition of alkyl Grignard reagents to α-methyl aldehydes afforded diastereomer ratios of threo/erythro