New simple syntheses of (E )-1-azido- (or thiocyanato)-alk-1-enes from alk-1-ynes by hydroboration

Abstract

Stereochemically pure (E )-1-azido- (or thiocyanato)-alk-1-enes have been synthesized in situ and in reasonable yields from alk-1-ynes upon hydroboration with disiamylborane followed by reactions with simple reagents; sodium azide (or potassium thiocyanate) and copper(II) nitrate trihydrate, in the presence of copper(II) acetate and a small amount of water, in polar aprotic solvents.

References

1. Recent reviews: A. Pelter, K. Smith and H. C. Brown, Borane Reagents, Academic Press, London, 1988; D. S. Matteson, Stereodirected Synthesis with Organoboranes, Springer, Berlin, 1995.
2. A. Suzuki, M. Ishidoya and M. Tabata, Synthesis, 1976, 687.
3. Y. Masuda, M. Hoshi and A. Arase, Bull. Chem. Soc. Jpn., 1984, 57, 1026.
4. A. Arase, Y. Masuda and A. Suzuki, Bull. Chem. Soc. Jpn., 1974, 47, 2511; A. Arase and Y. Masuda, Chem. Lett., 1976, 1115.
5. Y. Masuda, M. Hoshi and A. Arase, J. Chem. Soc., Perkin Trans. 1, 1992, 2725.
6. H. C. Brown, Organic Synthesis via Boranes, Wiley, New York, 1975, p. 54.
7. C. L. Jenkins and J. K. Kochi, J. Am. Chem. Soc., 1972, 94, 856.
8. G. W. Kabalka, T. M. Shoup and N. G. Goudgaon, Tetrahedron Lett., 1989, 1483.
9. For general synthesis and application of 2-azidoalk-1-enes [except for (E)-1-azido-3,3-dimethylbut-1-ene]via iodoalkyl azides see (a) F. W. Fowler, A. Hassner and L. A. Levy, J. Am. Chem. Soc., 1967, 89, 2077; A. Hassner and F. W. Fowler, J. Org. Chem., 1968, 33, 2686; (b) A. Hassner and F. W. Fowler, Tetrahedron Lett., 1967, 1545; J. Am. Chem. Soc., 1968, 90, 2869; J. Org. Chem., 1986, 51, 3176; A. Hassner, B. A. Belinka, Jr., M. Haber and P. Munger, Tetrahedron Lett., 1981, 22, 1863; Y. Nomura, Y. Takeuchi, S. Tomoda and M. M. Ito, Bull. Chem. Soc. Jpn., 1981, 54, 261.
10. (a) K. Tamao, T. Kakui and M. Kumada, Tetrahedron Lett., 1980, 111; (b) It has been shown that the formation of (E)-β-thiocyanatostyrene from 1-chloro-1-phenyl-2-thiocyanatoethane, itself derived from styrene, is possible: R. G. Guy and I. Pearson, Bull. Chem. Soc. Jpn., 1976, 49, 2310.
11. (a) S. Tomoda, Y. Matsumoto, Y. Takeuchi and Y. Nomura, Bull. Chem. Soc. Jpn., 1986, 59, 3283; (b) Although the stereochemistry is not obvious, it is demonstrated that azidostyrenes, ArCR=CHN₃, have been formed through the azido alcohol or the vinyl chloride: R. E. Bolton, C. J. Moody, M. Pass, C. W. Rees and G. Tojo, J. Chem. Soc., Perkin Trans. 1, 1988, 2491; A. L. Beck, W. J. Coates and C. J. Moody, J. Chem. Soc., Perkin Trans. 1, 1990, 689.
12. (a) T. K. Chakraborty and G. W. Reddy, Tetrahedron Lett., 1990, 1335; (b) It is reported that formation of (E)-β-azidostyrene from 1-bromo-1-phenyl-2-azidoethane, itself derived from styrene, is possible: A. Hassner, F. P. Boerwinkle and A. B. Levy, J. Am. Chem. Soc., 1970, 92, 4879.