On irradiation (350 nm) in the presence of 2,3-dimethylbuta-1,3-diene (8), 4-(alk-1-ynyl)coumarins 1 afford mixtures of cyclobuta-and cycloocta-annulated products 9 and 10, respectively. In contrast, the corresponding thiocoumarins 2 react with the same diene chemoselectively to give cyclohexa-annul
Ab initio vibrational analysis of trans- and gauche-2,3-dimethylbuta-1,3-diene
β Scribed by Charles W. Bock; Yurii N. Panchenko
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 546 KB
- Volume
- 221
- Category
- Article
- ISSN
- 0022-2860
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