Dimethyl dispiro[tricyclo[3.3.1.13,7]decane-1,2′-bicyclo[1.1.0]butane-4′,1′′-tricyclo[3.3.1.13,7]decane]-1′,3′-dicarboxylate, a strain-enhanced bicyclo[1.1.0]butane with a very short intramolecular C—H⃛H—C contact
Jan W. Bats, e-mail: [email protected]
Abstract
The title molecule, C26H34O4, shows a very short repulsive intramolecular C—H⃛H—C contact, with an H⃛H distance of only 1.71 Å. The flap angle ϕ of the bicyclo[1.1.0]butane group is widened to 131.23 (8)°. Both methylene C atoms show tilt angles of 6.1°. Bond lengths in the fused cyclopropane rings range from 1.501 (1) to 1.542 (1) Å and are influenced by π interactions with the carboxylate substituents.
