1. K. W. Bentley andH. M. E. Cardwell, J. chem. Soc.1955, 3252.
2. M. Shamma, Exper.16, 484 (1960).
3. C. Djerassi, K. Mislow, andM. Shamma, Exper.18, 53 (1961).
4. The numbering system adopted here is that recommended byA. M. Patterson, L. T. Capell, andD. F. Walker,The Ring Index (American Chemical Society, Washington D.C. 1959), p. 704, serial number 5171.
5. K. W. Bentley andS. F. Dyke, J. org. Chem.22, 429 (1957).