Rhodium(I)-catalysed alkylation of 2-vinylpyridines with alkenes as a result of C–H bond activation

Abstract

2-Vinylpyridines undergo regioselective β-alkylation with alkenes in the presence of a rhodium(I) complex as a catalyst to give products resulting from an anti-Markownikoff reaction. These results show the feasibility of alkylation of an alkenic position as a result of C–H bond activation. 2-(Prop-1-en-2-yl)pyridine 1 and 1-phenyl-1-(2-pyridyl)ethylene 15 react with linear terminal alkenes to give the corresponding alkylated products in high yields. Cyclic alkenes, allyl alcohol, but-3-en-1-ol and methyl vinyl ketone, however, fail to react with 1. Pent-2-ene gives the linear alkylated product in low yield. 6-Methyl-2-vinylpyridine 24 and 2-vinylpyridine 32 give the alkylated products in low yield together with their dimeric products. The alkenic C–H bond of 2-(cyclohex-1-enyl)pyridine 36 has been regioselectively alkylated. 2-(Cyclohex-1-enyl)pyridine 36 with alkenes in the presence of the Rh^I catalyst undergoes regiospecific alkylation at the alkenic position.

References

1. Y.-G. Lim., Y. H. Kim and J.-B. Kang, J. Chem. Soc., Chem. Commun., 1994, 2267; Y.-G. Lim, J.-B. Kang and Y. H. Kim, J. Chem. Soc., Perkin Trans. 1, 1996, 2201.
2. S. Murai, F. Kakiuchi, S. Sekine, Y. Tanaka, A. Kamatani, M. Sonoda and N. Chatani, Nature, 1993, 366, 529; S. Murai, F. Kakiuchi, S. Sekine, Y. Tanaka, A. Kamatani, M. Sonoda and N. Chatani, Pure Appl. Chem., 1994, 66, 1527; S. Murai, F. Kakiuchi, S. Sekine, Y. Tanaka, A. Kamatani, M. Sonoda and N. Chatani, Bull. Chem. Soc. Jpn., 1995, 68, 62; F. Kakiuchi, Y. Yamamoto, N. Chatani and S. Murai, J. Organomet. Chem., 1995, 504, 151; M. Sonoda, F. Kakiuchi, A. Kamatani, N. Chatani and S. Murai, Chem. Lett., 1996, 109; F. Kakiuchi, M. Yamauchi, N. Chatani and S. Murai, Chem. Lett., 1996, 111.
3. P. W. R. Harris and P. D. Woodgate, J. Organomet. Chem., 1997, 530, 211; P. W. R. Harris and P. D. Woodgate, J. Organomet. Chem., 1996, 506, 339.
4. H. Guo and W. P. Weber, Polym. Bull., 1994, 32, 525; H. Guo, M. A. Tapsak and W. P. Weber, Polym. Bull., 1995, 34, 49; H. Guo and W. P. Weber, Polym. Bull., 1995, 35, 259; H. Guo, M. A. Tapsak and W. P. Weber, Macromolecules, 1995, 28, 5856; H. Guo, M. A. Tapsak and W. P. Weber, Macromolecules, 1995, 28, 4174; G. Wang, H. Guo and W. P. Weber, J. Organomet. Chem., 1996, 521, 351; P. Lu, J. K. Paulasaari and W. P. Weber, Macromolecules, 1996, 29, 8583.
5. Y.-G. Lim, J.-B. Kang and Y. H. Kim, Chem. Commun., 1996, 585; This work was reported in part at the 73rd Annual Meeting of the Korean Chemical Society, April 22–23, Inha Univ., Incheon, Korea; Abstr. p. 246( 1994).
6. F. Kakiuchi, Y. Tanaka, T. Sato, N. Chatani and S. Murai, Chem. Lett., 1995, 679; N. Fujii, F. Kakiuchi, N. Chatani and S. Murai, Chem. Lett., 1996, 939; N. Fujii, F. Kakiuchi, A. Yamada, N. Chatani and S. Murai, Chem. Lett., 1997, 425.
7. B. M. Trost, K. Imi and I. W. Davies, J. Am. Chem. Soc., 1995, 117, 5371.
8. R. J. Foot and B. T. Heaton, J. Chem. Soc., Chem. Commun., 1973, 838; R. J. Foot and B. T. Heaton, J. Chem. Soc., Dalton Trans., 1979, 295; A. Albinati, C. Arz and P. S. Pregosin, J. Organomet. Chem., 1987, 335, 379; G. Jia, D. W. Meek and J. G. Gallucci, Organometallics, 1990, 9, 2549.
9. Y. Alvarado, O. Boutry, E. Gutierrez, A. Monge, M. C. Nicasio, M. L. Poveda, P. J. Perez, C. Ruiz, C. Bianchini and E. Carmona, Chem. Eur. J., 1997, 3, 860 and references cited therein.
10. A. E. Derome, Modern NMR Techniques for Chemistry Research, Pergamon Press, Oxford, 1987, pp. 121–122.
11. C. U. Pittman, Jr. and H. Akira, J. Org. Chem., 1978, 43, 640.
12. G. Raabe and J. Michl, Multiple Bonds to Silicon in the Chemistry of Organic Silicon Compounds, eds. S. Patai and Z. Rappoport, J. Wiley and Sons, New York, 1989, p. 10.
13. J. Halpern, Inorg. Chim. Acta, 1981, 50, 11.
14. J. Schwartz, D. W. Hart and J. L. Holden, J. Am. Chem. Soc., 1972, 94, 9269.
15. E. Hauptman, S. Sabo-Etienne, P. S. White, M. Brookhart, J. M. Garner, P. J. Fagan and J. C. Calabrese, J. Am. Chem. Soc., 1994, 116, 8038.
16. R. C. Larock, K. Oertle and G. F. Potter, J. Am. Chem. Soc., 1980, 102, 190.
17. E. Profft and H. W. Linke, Chem. Ber., 1960, 93, 2591.