Annulated bicyclo[2.2.2]octenones: 9-hydroxy-9-chloromethyl-endo-tricyclo[5.2.2.0^2,6]undeca-4,10-diene-3-spiro(1′-cyclopropane)-8-one and 12-hydroxy-12-chloromethyl-endo-tricyclo [8.2.2.0^2,9]tetradeca-13-en-11-one

Abstract

A single crystal X-ray diffraction study of two annulated bicyclo[2.2.2]octenones has been carried out to establish their precise stereostructures. The compounds, with their crystal data, are:1, 9-hydroxy-9-chloromethyl-endo-tricyclo[5.2.2.0^2,6]undeca-4,10-diene-3-spiro(1′-cyclopropane)-8-one, C₁₄H₁₅O₂Cl, space group P2₁/c,a=10.540(2),b=9.668(1),c=11.841(4)Å, β=95.67(2)°,Z=4, and2, 12-hydroxy-12-chloromethyl-endo-tricyclo[8.2.2.0^2,9]tetradeca-13-en-11-one, C₁₅H₂₁O₂Cl, space group C2/c,a=20.747(8),b=6.498(1),c=20.525(3)Å, β=93.04(3)°,Z=8. The molecule of1 has endo stereochemistry at the ring junction and the spirocyclopropane ring is proximal to the hydroxyl group. In2, the eight membered ring deviates from a chair conformation and one ring atom is disordered. Crystals of1 and2 contain centrosymmetric dimers formed by C=O...O−H hydrogen bonds.