The addition of Grignard reagents, hydride reagents and crotylstannanes to an alpha-alkoxy carbonyl bearing the 2-benzyloxytetrahydropyranyl group showed good levels of diastereofacial control. The sense of induction was the same as that reported for the addition of allylSnBu(3). An important solvent effect consistent with the proposed transition state model was observed in these reactions.