Transition structures of diastereoselective 1,3-dipolar cycloadditions of nitrile oxides to chiral homoallylic alcohols.
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].
Luft
Jennifer A R
JA
Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
Meleson
Kieche
K
Houk
K N
KN
D000438:Alcohols / Q000138:chemical synthesis*; D018360:Crystallography, X-Ray; D003500:Cyclization; D008274:Magnesium / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D009570:Nitriles / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000438:Alcohols; D009570:Nitriles; D008274:Magnesium