1. Y. Kitahara, I. Murata, and K. Shikanata, Bull. Chem. Soc. Jpn., 39, 629 (1966).
2. C. Lifshitz, E. D. Bergman, M. Rabinovitz, and I. Arganat, J. Chem. Soc., B, 723 (1968).
3. M. Neuenschwander, R. Vögeli, H. P. Fahrni, H. Lehman, and J. P. Ruder, Helv. Chim. Acta, 60, 1073 (1977).
4. H. O. Kalinovski and H. Kessler, Topics in Stereochemistry, 7, 299 (1973).
5. V. K. Shevtsov, P. I. Zakharov, V. P. Zvolinskii, V. G. Pleshakov, T. S. Seitembetov, and N. S. Prostakov, Khim. Geterotsikl. Soedin., No. 3, 397 (1979).