Stereoselective Synthesis of Substituted 3a-Hydroxy Diquinanones and 3a-Hydroxy Hydrindanones via Intramolecular Cycloaddition of Nitrile Oxides

Abstract

trans-1,3-Divinylcyclopentanes bearing a ω-nitroalkyl chain (C₂ or C₃) in the 2-position were submitted to an intramolecular nitrile oxide cycloaddition process to give tricyclic isoxazoline precursors of 4-hydroxymethylbicyclo[3.3.0]octan-1-ol-3-ones or 5-hydroxymethyl-9-vinylbicyclo[4.3.0]nonan-1-ol-4-ones.

Keywords:

• Diquinanones
• hydrindanones
• intramolecular cyloaddition
• nitrile oxides

ACKNOWLEDGMENTS

A.-S. C. is grateful to the CNRS and la Région PACA for grants. We are indebted to Dr. B. Vacher (Pierre Fabre Médicaments, Castres, France) for helpful comments. This work has been financially supported by the CNRS and the Ministère de l'Education Nationale.

Notes

^a B3LYP/6-311G++(p, d) level of the theory.

^b B3LYP/6-311G++(2df, 2pd) level of the theory.

^c Without ZPE correction.

^a w = 1/[σ ²(Fo²) + (0.1205P)² + 0.091P] where P = (Fo² + 2Fc²)/3.

^b w = 1/[σ ²(Fo²) + (0.0208P)² + 1.1795P] where P = (Fo² + 2Fc²)/3.

^c w = 1/[σ ²(Fo²) + (0.1007P)² + 2.9671P] where P = (Fo² + 2Fc²)/3.

^d w = 1/[σ ² (Fo ² ) + (0.0909P) ² +0.1063P] where P = (Fo² + 2Fc²)/3.