Abstract A variety of monosubstituted γ-lactols 4–6 were prepared in good yields by DIBAL reduction of the corresponding γ-lactones 1–3. The monophenyl-substituted lactols 4b–6b were transformed into disubstituted tetrahydrofuran derivatives by replacement of the hydroxyl group by the alkyl residue of organometallic compounds used as nucleophiles. The diastereoselectivity of the substitution was found to depend strongly on the substitution ...