Journalartikel

Jahr der Veröffentlichung: 2007

Seiten: 9533-9540

Zeitschrift: The Journal of Organic Chemistry

Bandnummer: 72

Heftnummer: 25

DOI Link: https://doi.org/10.1021/jo701615x

Verlag: American Chemical Society

Abstract: 

Based on systematic ab initio (CCSD(T)/cc-pVDZ) studies of substituent
effects, we present a concept for the construction of electronically
stabilized triplet ground state carbenes with singlet−triplet energy
separations (ΔE_ST) exceeding that of methylene.
Sterically demanding and conjugating substituents were excluded from the
selection of model compounds under investigation, as these either
destabilize both the singlet and the triplet states or delocalize
unpaired spins away from the carbene carbon. Negative partial charges on
the carbene center allow for the prediction of the electronic
stabilization of substituted carbenes. To decrease carbene reactivity,
we chose β-substituents with strong polar bonds. Among them, highly
electronegative elements such as fluorine and oxygen enlarge the ΔE_ST value with respect to hydrogen, while chlorine does not due to p-orbital participation.

Harvard-Zitierstil: Nemirowski, A. and Schreiner, P. (2007) Electronic Stabilization of Ground State Triplet Carbenes, The Journal of Organic Chemistry, 72(25), pp. 9533-9540. https://doi.org/10.1021/jo701615x

APA-Zitierstil: Nemirowski, A., & Schreiner, P. (2007). Electronic Stabilization of Ground State Triplet Carbenes. The Journal of Organic Chemistry. 72(25), 9533-9540. https://doi.org/10.1021/jo701615x