𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Quadricyclanes. Part II: Electronic structure and chemical reactivity

✍ Scribed by Edwin Haselbach; Hans-Dieter Martin

Publisher
John Wiley and Sons
Year
1974
Tongue
German
Weight
495 KB
Volume
57
Category
Article
ISSN
0018-019X

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

The electronic structure of quadricyclane and 3‐methylidenequadricyclane obtained by photoelectron spectroscopy, is used as a basis for the discussion of cycloadditions to these systems. The electronic structure of 3‐heteroquadricyclanes, arrived at by theoretical calculations, agrees well with that expected from the above measured systems. A surprising outcome is that the orbital most responsible for the observed 2,4‐cycloadditions to these heterosystems in not the HOMO but the third highest orbital which lies well below the former. This strongly suggests that these 2,4‐cycloadditions proceed not in a concerted fashion but presumably involve as rate‐determining step the formation of a resonance‐stabilized zwitterionic intermediate. The nature of this intermeiate is discussed and the feasability of its formation investigated on the basis of thermochemical considerations.

📜 SIMILAR VOLUMES

Quadricyclanes. Part I: Photoelectron sp
Quadricyclanes. Part I: Photoelectron spectra and electronic structure
✍ Hans-Dieter Martin; Constanze Heller; Edwin Haselbach; Zuzana Lanyjova 📂 Article 📅 1974 🏛 John Wiley and Sons 🌐 German ⚖ 345 KB

## Abstract The photoelectron spectra of quadricyclane (**3**) and 3‐methylidene quadricyclane (**4**) have been measured. The results served as a basis for the elucidation of the electronic structure of these compounds, which agreed with theoretical calculations. It is found that the symmetry of t