The boron—carbon triple bond (B̄C): Some theoretical predictions

✍ Scribed by Ian L. Alberts; Henry F. Schaefer III

• Book ID: 103026093
• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 544 KB
• Volume: 165
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(90)85438-i

✦ Synopsis

The structures of the organoboron anions HBCH and HBCBHz have been determined using ab initio methods that include the effects of dynamical electron correlation. Optimized geometries, electric dipole moments and harmonic vibrational frequencies are presented and discussed at the various levels of theory employed. The dependence ofthese molecular properties on the inclusion of diffuse functions in the basis set is investigated. The B-C bond lengths predicted at the highest consistent theoretical level, CISD/TZZP, are 1.319 A for HBCH and 1.338 and 1.467 8, for HBCBHI. It may be argued that the prototypical HBCH anion contains a formal B-C triple bond, while the larger HBCBH, anion incorporates a weaker B-C triple bond and a very strong C-B single bond. It is postulated that the partial bonding character in the diboro anion may be understood in terms of resonance structures and hyperconjugate interactions involving orbital overlap.