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Transition structures of diastereoselective 1,3-dipolar cycloadditions of nitrile oxides to chiral homoallylic alcohols.

ABSTRACT: Transition structures of the 1,3-dipolar cycloaddition of substituted nitrile oxides with chiral homoallylic alcohols were explored with density functional theory (B3LYP/6-311+G(d,p)+CPCM(dichloromethane)//B3LYP/6-31+G(d)). The diastereoselectivity observed in these reactions was explained. The anti product is favored in both the thermal and magnesium-mediated reactions. Selectivity is predicted to increase in the presence of magnesium, in agreement with experimental results. The energetics of the magnesium-mediated reaction are similar to those previously found for allylic alcohols. [structure: see text].

SUBMITTER: Luft JA

PROVIDER: S-EPMC2533356 | biostudies-literature | 2007 Feb

REPOSITORIES: biostudies-literature

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Transition structures of diastereoselective 1,3-dipolar cycloadditions of nitrile oxides to chiral homoallylic alcohols.

Luft Jennifer A R JA Meleson Kieche K Houk K N KN

Organic letters 20070125 4

Transition structures of the 1,3-dipolar cycloaddition of substituted nitrile oxides with chiral homoallylic alcohols were explored with density functional theory (B3LYP/6-311+G(d,p)+CPCM(dichloromethane)//B3LYP/6-31+G(d)). The diastereoselectivity observed in these reactions was explained. The anti product is favored in both the thermal and magnesium-mediated reactions. Selectivity is predicted to increase in the presence of magnesium, in agreement with experimental results. The energetics of t ...[more]

PMID: 17253700

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