Regiospecific synthesis and structural study of some trifluoromethyl substituted dibenzosemibullvalenes |
| |
| Authors: | Klaudio Otočan Mladen Mintas Fritz Kastner Albrecht Mannschreck James A Golen Paul G Williard |
| |
| Institution: | (1) Department of Organic Chemistry, University of Zagreb, 4100 Zagreb, Croatia;(2) Institute of Organic Chemistry, University of Regensburg, D-W-8400 Regensburg, Federal Republic of Germany;(3) Department of Chemistry, Brown University, 02912 Providence, Rhode Island, USA;(4) Present address: Department of Chemistry, Southeastern Massachusetts University, 02747 North Dartmouth, MA, USA |
| |
| Abstract: | Summary Preparation of the regiospecifically trifluoromethyl substituted dibenzosemibullvalenes3 and5 is described. An unequivocal proof of chirality of3 and5 was obtained by enrichment of their enantiomers using liquid chromatography on triacetyl- or tribenzoylcellulose. The stereostructure of compounds3 to5 was proved by their1H-NMR spectra and confirmed by X-ray crystallographic analysis. The geometrical data from X-ray structural analyses showed that five-membered rings involved in the skeleton of3 and5 adopt flattened envelope conformations. These results indicate also a significant substituent-induced bond length asymmetry in the cyclopropane rings of3 and5.Presented at the XIIIth IUPAC Symposium on Photochemistry, University of Warwick, Coventry, England, 1990 |
| |
| Keywords: | Dibenzobarrelene Dibenzosemibullvalene Enantioselective chromatography Trifluoromethylation Photochemical rearrangement X-ray crystal structures |
| 本文献已被 SpringerLink 等数据库收录！ |
|
