Copper(I)-catalyzed substitution of propargylic carbonates with diboron: Selective synthesis of multisubstituted allenylboronates

Journal of the American Chemical Society

Volumn 130, Issue 47, 2008, Pages 15774-15775

  Ito, Hajime ^a   Sasaki, Yusuke ^a   Sawamura, Masaya ^a  

^a HOKKAIDO UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

BORON DERIVATIVE; BORONIC ACID DERIVATIVE; CARBONIC ACID DERIVATIVE; CUPROUS ION;

ARTICLE; CATALYST; CHEMICAL ANALYSIS; CHEMICAL REACTION; CHEMICAL STRUCTURE; STEREOCHEMISTRY; SUBSTITUTION REACTION; SYNTHESIS;

EID: 56749169368     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja806602h     Document Type: Article

References (44)

1. For reviews of allenylmetals, see: (a) Marshall, J. A.; Gung, B. W.; Grachan, M. L. In Modern Allene Chemistry; Krause, N., Hashmi, A. S. K., Eds.; Wiley-VCH: Weinheim, 2004; Vol. 2, pp 493-592.
2. (b) Krause, N.; Hoffmann-Roder, A. Tetrahedron 2004, 60, 11671-11694.
3. (c) Brummond, K. M.; DeForrest, J. E. Synthesis 2007, 795-818.
4. (d) Marshall, J. A. J. Org. Chem. 2007, 72, 8153-8166.
5. For the synthesis of allenylboron compounds through the reaction of allenylmetals and boron electrophiles, see: (a) Ikeda, N.; Arai, I.; Yamamoto, H. J. Am. Chem. Soc. 1986, 108, 483-486.
6. (b) Corey, E. J.; Yu, C. M.; Lee, D. H. J. Am. Chem. Soc. 1990, 112, 878-879.
7. (c) Brown, H. C.; Khire, U. R.; Racherla, U. S. Tetrahedron Lett. 1993, 34, 15-18.
8. (d) Wang, K. K.; Liu, B.; Petersen, J. L. J. Am. Chem. Soc. 1996, 118, 6860-6867.
9. For rearrangements of alkynylboranes, see: (a) Leung, T.; Zweifel, G. J. Am. Chem. Soc. 1974, 96, 5620-5621.
10. (b) Midland, M. M. J. Org. Chem. 1977, 42, 2650-2651.
11. (c) Shimizu, M.; Kurahashi, T.; Kitagawa, H.; Hiyama, T. Org. Lett. 2003, 5, 225-227.
12. (d) Canales, E.; Gonzalez, A. Z.; Soderquist, J. A. Angew. Chem., Mt. Ed. 2007, 46, 397-399.
13. For hydroboration of 1-buten-3-ynes, see: (a) Satoh, M.; Nomoto, Y.; Miyaura, N.; Suzuki, A. Tetrahedron Lett. 1989, 30, 3789-3792.
14. (b) Matsumoto, Y.; Naito, M.; Hayashi, T. Organometallics 1992, 11, 2732-2734.
15. (c) Matsumoto, Y.; Naito, M.; Uozumi, Y.; Hayashi, T. Chem. Commun. 1993, 1468-1469.
16. We reported earlier efficient catalytic properties of the Cu(O-t-Bu)-Xantphos system in some reactions. For the dehydrogenative alcohol silylation with hydrosilanes, see: (a) Ito, H.; Watanabe, A.; Sawamura, M. Org. Lett. 2005, 7, 1869-1871.
17. For the regioselective and stereoselective reaction of allylic carbonates and a diboron, producing allylboron compounds and borylcyclopropanes, see: (b) Ito, H.; Kawakami, C.; Sawamura, M. J. Am. Chem. Soc. 2005, 127, 16034-16035.
18. (c) Ito, H.; Ito, S.; Sasaki, Y.; Matsuura, K.; Sawamura, M. J. Am. Chem. Soc. 2007, 129, 14856-14857.
19. (d) Ito, H.; Kosaka, Y.; Nonoyama, K.; Sasaki, Y.; Sawamura, M. Angew. Chem., Mt. Ed. 2008, 47, 7424-7427.
20. For the addition of terminal aIkynes to aldehyde, see: (e) Asano, Y.; Hara, K.; Ito, H.; Sawamura, M. Org. Lett. 2007, 9, 3901-3904.
21. (f) Asano, Y.; Ito, H.; Hara, K.; Sawamura, M. Organometallics 2008, 27, in press.
22. For studies with Cu(I)/Xantphos system by others, see: (g) Kim, D.; Park, B.; Yun, J. Chem. Commun. 2005, 1755-1757.
23. (h) Motoki, R.; Kanai, M.; Shibasaki, M. Org. Lett. 2007, 9, 2997-3000.
24. For selected studies on the synthesis of B compounds with Cu catalysis, see: (a) Ito, H.; Yamanaka, H.; Tateiwa, J.; Hosomi, A. Tetrahedron Lett. 2000, 41, 6821-6825.
25. (b) Takahashi, K.; Ishiyama, T.; Miyaura, N. Chem. Lett. 2000, 29, 982-983.
26. (c) Ramachandran, P. V.; Pratihar, D.; Biswas, D.; Srivastava, A.; Reddy, M. V. R. Org. Lett. 2004, 6, 481-484.
27. (d) Laitar, D. S.; Tsui, E. Y.; Sadighi, J. P. J. Am. Chem. Soc. 2006, 128, 11036-11037.
28. (e) Lee, J.; Yun, J. Angew. Chem., Mt. Ed. 2008, 47, 145-147.
29. (f) Lee, J.; Kwon, J.; Yun, J. Chem. Commun. 2008, 733-734.
30. There has been only one report for an α,γ,γ- trisubstituted allenylboron compound with alkyl substituents that differ from each other. See: Carrie, D.; Carboni, B.; Vaultier, M. Tetrahedron Lett. 1995, 36, 8209-8212.
31. Synthesis of axially chiral allenylboronates with moderate enantiomeric purities has been reported (refs 3c and 4c). For allenylboranes with a chiral auxiliary, see ref 3d.
32. For Lewis acid mediated reactions of allylboronates with aldehydes, see: (a) Ishiyama, T.; Ahiko, T.; Miyaura, N. J. Am. Chem. Soc. 2002, 124, 12414-12415.
33. (b) Kennedy, J. W. J.; Hall, D. G. J. Am. Chem. Soc. 2002, 124, 11586-11587.
34. (c) Hall, D. G. Synlett 2007, 1644-1655.
35. The reaction of substrates that have acetoxy or methoxy leaving groups instead of the carbonate resulted in lower yields even after longer reaction times (acetoxy: 88%, 24 h; methoxy: 53%, 48 h).
36. Directing effect of the phenyl group may have caused formation of a β-borylation intermediate. See ref 6f.
37. Low yields were due to the low reactivity of the di- and monosubstituted substrates. Unreacted starting materials were recovered.
38. For the synthesis of homopropargylic alcohols with allenyltin, allenylzinc, and allenylsilane reagents, see ref 1.
39. Crude allenylboronates that were obtained by short-pass silica gel chromatography were used.
40. 3), the reaction of 1n with benzaldehyde resulted in a lower yield of the product (4a) with a syn-selectivity (0°C, 44 h, 44%, antilsyn 16:84). The reaction of (S)-1h with isobutyraldehyde without the Lewis acid catalyst afforded the product ((3S,4R)-4d) in a moderate yield (0°C, 44 h, 61%) with a high enantiomeric purity (97% ee for anti product) and a slightly lower anti-selectivity (anti/syn 86:14) than that of the Lewis acid promoted reaction.
41. In the case of 4a and 4d, methanol (5.0 equiv) was added in the aldehyde addition. This slightly improved the syn/anti selectivities.
42. The carbonyl additions of allenylmetal reagents bearing a Lewis acidic metal group tend to favor production of anti-propargylic alcohols through cyclic transition states. However, anomalous syn-preference in the addition of allenyltitanium and allenylzinc reagents to benzaldehyde have been reported. See: (a) Furuta, K.; Ishiguro, M.; Haruta, R.; Ikeda, N.; Yamamoto, H. Bull. Chem. Soc. Jpn. 1984, 57, 2768-2776.
43. (b) Harada, T.; Katsuhira, T.; Osada, A.; Iwazaki, K.; Maejima, K.; Oku, A. J. Am. Chem. Soc. 1996, 118, 11377-11390.
44. Direct measurement of the enantiomeric purity of (S)-3h was unsuccessful because of its instability.