C. Shao et al. / Tetrahedron Letters 53 (2012) 2733–2735
2735
Yamamoto, H., sg, The, Jacobsen, E. N., Eds.; Springer: Berlin, 1999. Vols. 1–3;
(c) Ojima, I. In Catalytic Asymmetric Synthesis, 3rd ed.; John Wiley & Sons:
Hoboken, 2010.
high enantioselectivities (96–97% ee) were maintained when steri-
cally less hindered arylboronic acids were employed (entries 1–8).
Electron-donating or -withdrawing groups on the phenyl ring of
the arylboronic acids did not affect the reaction significantly. A
modest decrease in selectivity was observed when sterically
hindered 2-methoxyphenylboronic acid or 1-naphthylboronic acid
were used (entries 9 and 10). 2-Cyclopentenone (4b) and 5,6-dihy-
dro-2H-pyran-2-one (4c) were also suitable substrates and gave
the addition product in 83% ee and 88% ee, respectively (entries
11 and 12). We observed that the enantioselectivity in the addition
of arylboronic acid to linear enone 4d was greatly affected by the
steric properties of the arylboronic acid (16% ee with phenylbo-
ronic acid vs 87% ee with 2-methylphenylboronic acid), albeit high
reaction yields were observed in both cases (entries 13 and 14).
In summary, a variety of novel C1-symmetric chiral diene
ligands based on the DCP skeleton were easily prepared from
cheap, commercially available starting materials. These new
ligands were successfully applied in the rhodium-catalyzed
2. (a) Hayashi, T.; Ueyama, K.; Tokunaga, N.; Yoshida, K. J. Am. Chem. Soc. 2003,
125, 11508; (b) Fisher, C.; Defieber, C.; Suzuki, T.; Carreira, E. M. J. Am. Chem.
Soc. 2004, 126, 1628.
3. For reviews on chiral diene ligands, see: (a) Glorius, F. Angew. Chem., Int. Ed.
2004, 43, 3364; (b) Defieber, C.; Grützmacher, H.; Carreira, E. M. Angew. Chem.,
Int. Ed. 2008, 47, 4482; (c) Shintani, R.; Hayashi, T. Aldrichim. Acta 2009, 42, 31;
(d) Feng, C.-G.; Xu, M.-H.; Lin, G.-Q. Synlett 2011, 1345.
4. For selected recent examples on chiral diene ligands, see (a) Shintani, R.;
Takeda, M.; Soh, Y.-T.; Ito, T.; Hayashi, T. Org. Lett. 2011, 13, 2977; (b) Shao, C.;
Yu, H.-J.; Wu, N.-Y.; Tian, P.; Wang, R.; Feng, C.-G.; Lin, G.-Q. Org. Lett. 2011, 13,
788; (c) Cui, Z.; Yu, H.-J.; Yang, R.-F.; Gao, W.-Y.; Feng, C.-G.; Lin, G.-Q. J. Am.
Chem. Soc. 2011, 133, 12394; (d) Li, Q.; Dong, Z.; Yu, Z.-X. Org. Lett. 2011, 13,
1122; (e) Luo, Y.; Carnell, A. J. Angew. Chem., Int. Ed. 2010, 49, 2750; (f) Shintani,
R.; Isobe, S.; Takeda, M.; Hayashi, T. Angew. Chem., Int. Ed. 2010, 49, 3795; (g)
Nishimura, T.; Wang, J.; Nagaosa, M.; Okamoto, K.; Shintani, R.; Kwong, F.; Yu,
W.; Chan, A. S. C.; Hayashi, T. J. Am. Chem. Soc. 2010, 132, 464; (h) Nishimura, T.;
Makino, H.; Nagaosa, M.; Hayashi, T. J. Am. Chem. Soc. 2010, 132, 12865; (i)
Shintani, R.; Takeda, M.; Tsuji, T.; Hayashi, T. J. Am. Chem. Soc. 2010, 132, 13168;
(j) Pattison, G.; Piraux, G.; Lam, H. W. J. Am. Chem. Soc. 2010, 132, 14373; (k)
Cao, Z.-P.; Du, H.-F. Org. Lett. 2010, 12, 2602.
5. For selected recent examples of heteroatom–olefin hybrid ligands, see: (a)
Shintani, R.; Narui, R.; Tsutsumi, Y.; Hayashi, S.; Hayashi, T. Chem. Commun.
2011, 47, 6123; (b) Liu, Z.; Cao, Z.; Du, H. Org. Biomol. Chem. 2011, 9, 5369; (c)
Nishimura, T.; Maeda, Y.; Hayashi, T. Org. Lett. 2011, 13, 3674; (d) Drinkel, E.;
Briceno, A.; Dorta, R.; Dorta, R. Organometallics 2010, 29, 2503; (e) Jin, S.-S.;
Wang, H.; Xu, M.-H. Chem. Commun. 2011, 47, 7230; (f) Thaler, T.; Guo, L.-N.;
Steib, A. K.; Raducan, M.; Karaghiosoff, K.; Mayer, P.; Knochel, P. Org. Lett. 2011,
13, 3182; (g) Feng, X.; Wang, Y.; Wei, B.; Yang, J.; Du, H. Org. Lett. 2011, 13,
3300; (h) Hahn, B. T.; Tewes, F.; Froehlich, R.; Glorius, F. Angew. Chem., Int. Ed.
2010, 49, 1143.
asymmetric 1,4-addition of arylboronic acids to
a,b-unsaturated
carbonyl compounds. Under mild reaction conditions, the
desired addition products were generated in high yields
(90–99%) with high enantioselectivities (up to 97% ee). Further
applications of these readily available chiral dienes in asymmetric
synthesis are currently under investigation.
Acknowledgments
6. (a) Tokunaga, N.; Otomaru, Y.; Okamoto, K.; Ueyama, K.; Shintani, R.; Hayashi,
T. J. Am. Chem. Soc. 2004, 126, 13584; (b) Wang, Z.-Q.; Feng, C.-G.; Xu, M.-H.;
Lin, G.-Q. J. Am. Chem. Soc. 2007, 129, 5336.
7. (a) For selected examples, see: Ref. 2b.; (b) Okamoto, K.; Hayashi, T.; Rawal, V.
H. Org. Lett. 2008, 10, 4387.
8. (a) For selected examples, see: Ref. 2a.; (b) Brown, M. K.; Corey, E. J. Org. Lett.
2010, 12, 172.
9. For selected examples, see: (a) Otomaru, Y.; Okamoto, K.; Shintani, R.; Hayashi,
T. J. Org. Chem. 2005, 70, 2503; (b) Nishimura, T.; Kumamoto, H.; Nagaosa, M.;
Hayashi, T. Chem. Commun. 2009, 5713.
Financial support from The Major State Basic Research Develop-
ment Program (2010CB833302), the National Natural Science
Foundation of China (21002112) and Shanghai Municipal Commit-
tee of Science and Technology (09JC1417300) is acknowledged.
Supplementary data
10. For selected examples, see: (a) Feng, C.-G.; Wang, Z.-Q.; Tian, P.; Xu, M.-H.; Lin,
G.-Q. Chem. Asian J. 2008, 3, 1511. (b) Ref. 4e.
Supplementary data (experimental procedures, characteriza-
tion data; 1H and 13C spectra for new compounds) associated with
11. Shao, C.; Yu, H.-J.; Wu, N.-Y.; Feng, C.-G.; Lin, G.-Q. Org. Lett. 2010, 12, 3820.
12. For leading reviews on Rh-catalyzed asymmetric conjugated additions, see: (a)
Hayashi, T.; Yamasaki, K. Chem. Rev. 2003, 103, 2829; (b) Gennari, C.; Monti, C.;
Piarulli, U. Pure Appl. Chem. 2006, 78, 303; (c) Christoffers, J.; Koripelly, G.;
Rosiak, A.; Rössle, M. Synthesis 2007, 1279; (d) Edwards, H. J.; Hargrave, J. D.;
Penrose, S. D.; Frost, C. G. Chem. Soc. Rev. 2010, 39, 2093.
13. For examples with KHF2 as additive, see: (a) Su, Y.; Jiao, N. Org. Lett. 2009, 11,
2980; (b) Wang, Z. Q.; Feng, C. G.; Zhang, S. S.; Xu, M. H.; Lin, G. Q. Angew.
Chem., Int. Ed. 2010, 49, 5780.
References and notes
1. (a) Noyori, R. In Asymmetric Catalysis in Organic Synthesis; Wiley: New York,
1994. 2nd ed.; (b)Comprehensive Asymmetric Catalysis; Jacobsen, E. N., Pfaltz, A.,