Intramolecular carbene stabilization via 3c,2e bonding on basis of the magnetic criterion
- The spatial magnetic properties, through-space NMR shieldings (TSNMRS), of bent cyclobutylcarbene 8, 1,2-diboretane-3-ylidene 9, and some carbene analogues of boron 14-18 as most intriguing examples of carbenes, which can be stabilized as homoaromatic systems with 3c,2e bonding, have been calculated using the GIAO perturbation method employing the nucleus independent chemical shift (NICS) concept and the results visualized as iso-chemical-shielding surfaces (ICSS) of various size and direction. The TSNMRS values (actually, ring current effect/anisotropy effects as measurable in H-1 NMR spectroscopy) are employed to qualify and quantify the degree of present 3c,2e-homoaromaticity. Results are confirmed by geometry (bond angles and bond lengths) and spectroscopic data, the delta(B-11)/ppm data and the C-13 chemical shifts of the carbene electron-deficient centre.
| Verfasserangaben: | Erich KleinpeterORCiDGND, Andreas Koch |
|---|---|
| DOI: | https://doi.org/10.1016/j.tet.2021.132357 |
| ISSN: | 0040-4020 |
| ISSN: | 1464-5416 |
| Titel des übergeordneten Werks (Englisch): | Tetrahedron : the international journal for the rapid publication of full original research papers and critical reviews in organic chemistry |
| Verlag: | Elsevier Science |
| Verlagsort: | Amsterdam |
| Publikationstyp: | Wissenschaftlicher Artikel |
| Sprache: | Englisch |
| Datum der Erstveröffentlichung: | 20.07.2021 |
| Erscheinungsjahr: | 2021 |
| Datum der Freischaltung: | 01.02.2023 |
| Freies Schlagwort / Tag: | 1,2-diboretane-3-ylidene; 3c,2e-bonding; Cyclobutylcarbene; NICS; Through-space NMR shieldings (TSNMRS) |
| Band: | 95 |
| Aufsatznummer: | 132357 |
| Seitenanzahl: | 9 |
| Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
| DDC-Klassifikation: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
| Peer Review: | Referiert |
