Autor: |
Angel L. Esteban, Ian J. Lochert, Ernesto Díez, Rubén H. Contreras, Ernest W. Della |
Rok vydání: |
2004 |
Předmět: |
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Zdroj: |
Magnetic resonance in chemistry : MRC. |
ISSN: |
0749-1581 |
Popis: |
(13)C chemical shifts were measured for 18 1-X,3-CH(3)-bicyclo[1.1.1]pentanes and the corresponding (13)C substituent chemical shifts (SCSs) were compared with those measured previously for the corresponding 1-X-bicyclo[1.1.1]pentanes. DFT-B3LYP calculations of GIAO magnetic shielding constants and of natural bond orbitals were carried out in order to gain an insight into factors defining the observed differences in (13)C SCSs in both series. These differences are rationalized in terms of substituent effects on sigma-hyperconjugative interactions. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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