Bishomoaromatic 1,2,4-Triboracyclopentane Dianions: Strong Three-Center, Two-Electron Bonds between Three Boron Atoms
✍ Scribed by David Scheschkewitz; Abolfazl Ghaffari; Peter Amseis; Markus Unverzagt; Govindan Subramanian; Matthias Hofmann; Paul von Ragué Schleyer; Henry F. Schaefer III; Gertraud Geiseler; Werner Massa; Armin Berndt
- Publisher
- John Wiley and Sons
- Year
- 2000
- Tongue
- English
- Weight
- 128 KB
- Volume
- 39
- Category
- Article
- ISSN
- 0044-8249
No coin nor oath required. For personal study only.
✦ Synopsis
The three-center, two-electron (3c,2e) bonding of bishomoaromatic cations of type 1 [1±4] are known to be weakened by R C 6 H 5 [2b, 3a] and displaced by R p-MeOC 6 H 4 and R OH. [4] Evidently, cations 1 are stabilized by the 3c,2e bonds, whereas cations 2 are stabilized by donor substituents R. According to computational estimates, 1 u (R H) is more stable than 2 u (R H) by 15 kcal mol À1 . [2a] The energy difference between the prototypes 3 u and 4 u, neither of which is known experimentally, is only 10.1 kcal mol À1 . [5] C