Catalytic asymmetric boration of acyclic α,β-unsaturated esters and nitriles

Angewandte Chemie - International Edition

Volumn 47, Issue 1, 2008, Pages 145-147

  Lee, Ji Eon ^a   Yun, Jaesook ^a  

^a Sungkyunkwan University   (South Korea)

Author keywords

Asymmetric catalysis; Boron; Conjugate addition; Copper; Unsaturated carbonyl compounds

Indexed keywords

BORON; CATALYST ACTIVITY; COPPER; UNSATURATED COMPOUNDS;

ASYMMETRIC CATALYSIS; CONJUGATE ADDITION; UNSATURATED CARBONYL COMPOUNDS;

ESTERS;

EID: 37549021866     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.200703699     Document Type: Article

References (22)

1. For reviews, see: a) I. Beletskaya, C. Moberg, Chem. Rev. 2006, 106, 2320-2354;
2. b) G. J. Irvine, M. J. G. Lesley, T. B. Marder, N. C. Norman, C. R. Rice, E. G. Robins, W. R. Roper, G. R. Whittell, L. J. Wright, Chem. Rev. 1998, 98, 2685-2722;
3. c) I. Beletskaya, C. Moberg, Chem. Rev. 1999, 99, 3435-3461;
4. d) Contemporary Boron Chemistry (Eds.: M. Davidson, A. K. Hughes, T. B. Marder, K. Wade). RSC Cambridge, 2000.
5. a) Y. G. Lawson, M. J. G. Lesley, T. B. Marder, N. C. Norman, C. R. Rice, Chem. Commun. 1997, 2051-2052;
6. b) H. Abu Ali, I. Goldberg, M. Srebnik, Organometallics 2001, 20, 3962-3965;
7. c) N. J. Bell, A. J. Cox, N. R. Cameron, J. S. O. Evans, T. B. Marder, M. A. Duin, C. J. Elsevier, X. Baucherel, A. A. D. Tulloch, R. P. Tooze, Chem. Commun. 2004, 1854-1855.
8. G. W. Kabalka, B. C. Das, S. Das, Tetrahedron Lett. 2002, 43, 2323-2325.
9. a) H. Ito, H. Yamanaka, J. Tateiwa, A. Hosomi, Tetrahedron Lett. 2000, 41, 6821-6825;
10. b) K. Takahashi, T. Ishiyama, N. Miyaura, J. Organomet. Chem. 2001, 625, 47-53.
11. S. Mun, J.-E. Lee, J. Yun, Org. Lett. 2006, 8, 4887-4889.
12. a) Organoboranes for syntheses, ACS symposium series 783 (Eds.: P. V. Ramachandran, H. C. Brown), American Chemical Society, Washington, DC, 2001;
13. b) H. C. Brown, B. Singaram, Acc. Chem. Res. 1988, 21, 287-293.
14. a) D. Lee, D. Kim, J. Yun, Angew. Chem. 2006, 118, 2851-2853;
15. Angew. Chem. Int. Ed. 2006, 45, 2785-2787;
16. b) D. Lee, Y. Yang, J. Yun, Synthesis 2007, 2233-2235;
17. c) D. Lee, Y. Yang, J. Yun, Org. Lett. 2007, 9, 2749-2751.
18. Other diphosphine ligands, such as various josiphos analogues and binap, were also surveyed in the boron addition reaction with 1e but gave poorer enantioselectivities (less than 50% ee). In this case, the best result was again obtained with josiphos. Other ligands, such as 2-(diphenylphosphino- 2′-methoxy-1,1′-binaphthyl) (mop) and binapthol-derived phosphoramidite, gave incomplete conversion and very low asymmetric inductions (less than 7 % ee).
19. The condition A gave slightly better enantioselectivities (0-2% ee) than the reaction conditions using the 1:1.5:1 combination of copper/base/L1.
20. C. N. Farthing, S. P. Marsden, Tetrahedron Lett. 2000, 41, 4235-4238.
21. The major enantiomer of the other unknown products 3 was assumed to have the same configuration as the known cases (3a, 3b, 3d, 3e, and 3i).
22. With the ester substrates, longer reaction times (16-24 h) were required than with the nitriles substrates (less than 12 h) for complete conversion.