R. Brown, G. Fallon, B. M. Gatehouse
1982
Citations
0
Influential Citations
5
Citations
Journal
Australian Journal of Chemistry
Abstract
The cyclopropa[c]benzofuran derivative (17), which contains the structural features of methyl ethers of mycorrhizin A and gilmicolin save for the C3 side chain, has been synthesized from the benzofuranol (4) through the benzofuran-4,7-dione (5) and the 7a-methoxy derivative (8). The cyclopropane ring of (17) was introduced by ultraviolet irradiation of a 1-pyrazoline (13) at -78o; irradiation at room temperature gave mainly a profoundly rearranged acidic product for which the methanoindenone structure (18) is proposed. The stereochemistry of the penultimate cyclopropane (16) has been established by X-ray crystallography.