Hydrogen bonding. Part 83. The bis-troponehydrogen cation: preparation, IR, and MO study of a proton bridged dimer of tropone with a covalent three-center OHO bond

Admixture of equal parts of liquid tropone and solid hydroxytropylium perchlorate gives a quantitative yield of a homogeneous white crystalline material; infrared spectra demonstrate that neither starting material is present in the new substance in its original form. Ab initio molecular orbital treatment supports a formulation as the perchlorate salt of a proton bridged cationic dimer of tropone with a nearly symmetrical three-center OHO bond and a attraction energy of about 230 kcal mol21. q 2004 Elsevier B.V. All rights reserved