Cyclopropanes: Calculation of NMR spectra by ab initio methodology

✍ Scribed by Ronald R. Sauers

• Publisher: Elsevier Science
• Year: 1998
• Tongue: French
• Weight: 705 KB
• Volume: 54
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(97)10276-9

✦ Synopsis

1H and 13C nuclear magnetic resonance chemical shifts for a select group of cyclopropyl systems were calculated using ab initio/gauge-independent atomic orbital methodology. Long range nucleus independent chemical shifts attributable to cyclopropane ring currents were estimated. The results demonstrate the viability of this protocol to simulate unusual long range shielding/deshielding effects associated with cyclopropyl systems. Examination of the molecular orbitals of bicyclo[3.1.0]hexyl systems revealed a highly delocalized HOMO for the anti-conformer (pseudochair form). Natural atomic population analyses were used to examine putative correlations between atomic charges and chemical shifts.