A new strategy for construction of angularly fused tricyclic ring systems. Transannular bond formation of bicyclic enones via photochemical intramolecular hydrogen abstraction
✍ Scribed by Yoshito Tobe; Takayuki Iseki; Kiyomi Kakiuchi; Yoshinobu Odaira
- Book ID
- 104242387
- Publisher
- Elsevier Science
- Year
- 1984
- Tongue
- French
- Weight
- 163 KB
- Volume
- 25
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
✦ Synopsis
Tricyclic ketones 3 B and 2-s having angularly fused 5-6-5 or 5-7-5 ring system have been efficiently prepared by irradiation of bicyclic enones _& and 1. Angularly fused tricyclic ring systems have been attracted increasing interest because many natural products which possess this new type of carbon frameworks composed of a variety of constituent rings have been found in recent years, 1 We report herein a new strategy for construction of angularly fused 5-6-5 and 5-7-5 ring systems from reasily available bicyclic enones Land &2 Namely, the above systems could be formed by transannular C-C bond formation in the diradical intermediate generated by photochemical intramolecular hydrogen abstraction at B-carbon atom3 of enones A and 2 as shown below.