168
H. N. Naziroglu et al. / Tetrahedron: Asymmetry 23 (2012) 164–169
(Chiralcel OD-H), Hexane/i-PrOH 90:10, UV 254 nm, 1 ml/min, syn-
1 ml/min, syn-isomer: tminor = 20.3 min and tmajor = 25.3 min, anti-
isomer: tmajor = 30.8 min; 89 % ee.
isomer: tminor = 21.8 min and tmajor = 24.3 min, anti-isomer: tmajor
26.4 min; 85 % ee.
=
4.3.13. (2R,3S)-3-(4-Methoxyphenyl)-2-methyl-4-nitrobutanal
4l
4.3.8. (2R,3S)-(4-Bromophenyl)-2-methyl-4-nitrobutanal 4g
Compound 4g was prepared according to the general procedure
from propanal and trans-1-bromo-4-(2-nitrovinyl) benzene to pro-
vide the title compound (83% yield) after flash column chromatog-
raphy on silica gel (petroleum ether/ethyl acetate = 9:1). 1H NMR
(400 MHz, CDCl3) d: 9.67 (d, 1H, J = 1.1 Hz), 7.45 (d, 1H,
J = 8.4 Hz), 7.03 (d, 1H, J = 8.4 Hz), 4.57–4.80 (m, 2H), 3.71–3.81
(m, 1H), 2.67–2.81 (m, 1H), 0.98 (d, 3H, J = 7.3 Hz). The enantio-
meric excess was determined by HPLC (Chiralcel AD-H), Hexane/
i-PrOH 95:5, UV 254 nm, 0.5 ml/min, syn-isomer: tmajor = 32.7 min
Compound 4l was prepared according to the general procedure
from propanal and trans-1-methoxy-4-(2-nitrovinyl) benzene to
provide the title compound (85% yield) after flash column chroma-
tography on silica gel (petroleum ether/ethyl acetate = 9:1). 1H
NMR (400 MHz, CDCl3) d: 9.70 (d, 1H, J = 1.7 Hz), 7.08 (d, 2H,
J = 8.7 Hz), 6.84 (d, 2H, J = 8.8 Hz), 4.59–4.77 (m, 2H), 3.72–3.80
(m, 4H), 2.69–2.77 (m, 1H), 0.95 (d, 3H, J = 7.3 Hz). The enantio-
meric excess was determined by HPLC (Chiralcel OD-H), Hexane/
i-PrOH 90:10, UV 254 nm, 1 ml/min, syn-isomer: tminor = 28.8 min
and tminor = 47.1 min, anti-isomer: tminor = 38.3 min and tmajor
42.8 min; 99 % ee.
=
and tmajor = 30.6 min, anti-isomer: tmajor = 36.6 min and tminor
38.6 min; 90 % ee.
=
4.3.9. (2R,3S)-(3-Bromophenyl)-2-methyl-4-nitrobutanal 4h
Acknowledgment
Compound 4h was prepared according to the general procedure
from propanal and 1-bromo-3-(2-nitrovinyl)-benzene to provide
the title compound (95% yield) after flash column chromatography
on silica gel (petroleum ether/ethyl acetate = 8:1). 1H NMR
(400 MHz, CDCl3) d: 9.69 (s, 1H), 7.43 (d, 1H, J = 7.9 Hz), 7.33 (s,
1H), 7.30–7.18 (m, 1H), 7.12 (d, 1H, J = 7.9 Hz), 4.79 (dd, 1H,
J = 1.3 and 12.9 Hz), 4.65 (dd, 1H, J = 9.6 and 12.8 Hz), 3.88–3.70
(m, 1H), 2.86–2.70 (m, 1H), 1.01 (d, 3H, J = 7.2 Hz). The enantio-
meric excess was determined by HPLC (Chiralcel AD-H), Hexane/
i-PrOH 95:5, UV 254 nm, 0.5 ml/min, syn-isomer: tmajor = 28.9 min
We are grateful for the grants from the Scientific and Technical
Research Council of Turkey (TUBITAK–109T167).
References
1. (a) Berkessel, A.; Groger, H. Asymmetric Organocatalysis: From Biomimetic
Concepts to Applications in Asymmetric Synthesis; Wiley-VCH GmbH & Co. KGaA:
Weinheim, Germany, 2005; (b) Dalko, P. I.; Moisan, L. Angew. Chem., Int. Ed.
2004, 43, 5138–5175; (c) Houk, K. N.; List, B. Acc. Chem. Res. 2004, 37, 487; (d)
List, B. Chem. Commun. 2006, 819–824; (e) Palomo, C.; Oiarbide, M.; Lopez, R.
Chem. Soc. Rev. 2009, 38, 632–653; (f) Piovesana, S.; Schietroma, D. M. S.; Bella,
M. Angew. Chem., Int. Ed. 2011, 50, 6216–6232; (g) Almaßsi, D.; Alonso, D. A.;
Najera, C. Tetrahedron: Asymmetry 2007, 18, 299–365.
and tminor = 32.0 min, anti-isomer: tminor = 21.1 min and tmajor
22.1 min; 68 % ee.
=
2. (a) Berner, O. M.; Tedeschi, L.; Enders, D. Eur. J. Org. Chem. 2002, 1877–1894; (b)
Li, P.; Wang, L.; Wang, M.; Zhang, Y. Eur. J. Org. Chem. 2008, 1157–1160.
3. Sakthivel, K.; Notz, W.; Bui, T.; Barbas, C. F., III J. Am. Chem. Soc. 2001, 123,
5260–5267.
4. List, B.; Pojarliev, P.; Martin, H. J. Org. Lett. 2001, 3, 2423–2425.
5. (a) Luo, S.; Xu, H.; Mi, X.; Li, J.; Zheng, X.; Cheng, J. P. J. Org. Chem. 2006, 71,
9244–9247; (b) Yan, Z. Y.; Niu, Y. N.; Wei, H. L.; Wu, L. Y.; Zhao, Y. B.; Liang, Y.
M. Tetrahedron: Asymmetry 2006, 17, 3288–3293.
6. (a) Cobb, A. J. A.; Longbottom, D. A.; Shaw, D. M.; Ley, S. V. Chem. Commun.
2004, 1808–1809; (b) Cobb, A. J. A.; Shaw, D. M.; Longbottom, D. A.; Gold, J. B.;
Ley, S. V. Org. Biomol. Chem. 2005, 3, 84–96; (c) Mitchell, C. E. T.; Cobb, A. J. A.;
Ley, S. V. Synlett 2005, 611–614.
7. (a) Betancort, J. M.; Barbas, C. F., III Org. Lett. 2001, 3, 3737–3740; (b) Betancort,
J. M.; Sakthivel, K.; Thayumanavan, R.; Tanaka, F.; Barbas, C. F., III Synthesis
2004, 1509–1521; (c) Mase, N.; Thayumanavan, R.; Tanaka, F.; Barbas, C. F., III
Org. Lett. 2004, 6, 2527–2530; (d) Pansare, S. V.; Pandya, K. J. Am. Chem. Soc.
2006, 128, 9624–9625; (e) Mase, N.; Watanabe, K.; Yoda, H.; Takabe, K.; Tanaka,
F., ; Barbas, C. F., III J. Am. Chem. Soc. 2006, 128, 4966–4967; (f) Zhu, M. K.; Cun,
L. F.; Mi, A. Q.; Jiang, Y. Z.; Gong, L. Z. Tetrahedron: Asymmetry 2006, 17, 491–
493; (g) Vishnumaya; Singh, V. K. Org. Lett. 2007, 9, 1117–1119.
4.3.10. (2R,3S)-(2-Bromophenyl)-2-methyl-4-nitrobutanal 4i
Compound 4i was prepared according to the general procedure
from propanal and 1-bromo-2-(2-nitrovinyl)-benzene to provide
the title compound (90% yield) after flash column chromatography
on silica gel (petroleum ether/ethyl acetate = 8:1). 1H NMR
(400 MHz, CDCl3) d: 9.73 (s, 1H), 7.60 (d, 1H, J = 8.0 Hz), 7.36–
7.28 (m, 1H), 7.24–7.12 (m, 2H), 4.86–4.78 (m, 1H), 4.77 (dd, 1H,
J = 4.8 and 12.9 Hz), 4.46–4.38 (m, 1H), 3.02–2.96 (m, 1H), 1.04
(d, 3H, J = 7.4 Hz). The enantiomeric excess was determined by
HPLC (Chiralcel AD-H), Hexane/i-PrOH 95:5, UV 254 nm, 0.5 ml/
min, syn-isomer: tmajor = 23.6 min and tminor = 26.9 min, anti-iso-
mer: tminor = 28.3 min and tmajor = 30.4 min; 98 % ee.
4.3.11. (2R,3S)-(4-Chlorophenyl)-2-methyl-4-nitrobutanal 4j
Compound 4j was prepared according to the general procedure
from propanal and 1-chloro-4-(2-nitrovinyl)-benzene to provide
the title compound (81% yield) after flash column chromatography
on silica gel (petroleum ether/ethyl acetate = 10:1). 1H NMR
(400 MHz, CDCl3) d: 9.70 (d, 1H, J = 1.5 Hz), 7.32 (d, 2H,
J = 10 Hz), 7.11 (d, 2H, J = 8.5 Hz), 4.58–4.84 (m, 2H), 3.73–3.85
(m, 1H), 2.71–2.80 (m, 1H), 1.01 (d, 3H, J = 7.3 Hz). The enantio-
meric excess was determined by HPLC (Chiralcel AD-H), Hexane/
i-PrOH 95:5, UV 254 nm, 0.5 ml/min, syn-isomer: tmajor = 30.5 min
and tminor = 39.8 min; 68 % ee.
8. (a) Alexakis, A.; Andrey, O. Org. Lett. 2002, 4, 3611–3614; (b) Andrey, O.;
Vidonne, A.; Alexakis, A. Tetrahedron Lett. 2003, 44, 7901–7904; (c) Andrey, O.;
Alexakis, A.; Bernardinelli, G. Org. Lett. 2003, 5, 2559–2561; (d) Andrey, O.;
Alexakis, A.; Tomassini, A.; Bernardinelli, G. Adv. Synth. Catal. 2004, 346, 1147–
1168; (e) Mossé, S.; Laars, M.; Kriis, K.; Kanger, T.; Alexakis, A. Org. Lett. 2006, 8,
2559–2562; (f) Mossé, S.; Alexakis, A. Org. Lett. 2006, 8, 3577–3580; (g) Mossé,
S.; Alexakis, A. Chem. Commun. 2007, 3123–3135.
9. Ishii, T.; Fujioka, S.; Sekiguchi, Y.; Kotsuki, H. J. Am. Chem. Soc. 2004, 126, 9558–
9559.
10. (a) Wang, W.; Wang, J.; Li, H. Angew. Chem., Int. Ed. 2005, 44, 1369–1371; (b)
Zu, L.; Wang, J.; Li, H.; Wang, W. Org. Lett. 2006, 8, 3077–3079; (c) Wang, J.; Li,
H.; Lou, B. S.; Zu, L.; Guo, H.; Wang, W. Chem. Eur. J. 2006, 12, 4321–4332; (d)
Diez, D.; Gil, M. J.; Moro, R. F.; Marcos, I. S.; García, P.; Basabe, P.; Garrido, N. M.;
Broughton, H. B.; Urones, J. G. Tetrahedron 2007, 63, 740–747; (e) Ni, B.; Zhang,
Q.; Headley, A. D. Tetrahedron: Asymmetry 2007, 18, 1443–1447; (f) Wang, C.;
Yu, C.; Liu, C.; Peng, Y. Tetrahedron Lett. 2009, 50, 2363–2366.
11. (a) Okino, T.; Hoashi, Y.; Takemoto, Y. J. Am. Chem. Soc. 2003, 125, 12672–
12673; (b) Wang, J.; Li, H.; Duan, W.; Zu, L.; Wang, W. Org. Lett. 2005, 7, 4713–
4716; (c) Tsogoeva, S. B.; Wei, S. Chem. Commun. 2006, 1451–1453; (d) Lalonde,
M. P.; Chen, Y.; Jacobsen, E. N. Angew. Chem., Int. Ed. 2006, 45, 6366–6370; (e)
Huang, H.; Jacobsen, E. N. J. Am. Chem. Soc. 2006, 128, 7170–7171; (f) Cao, C. L.;
Ye, M. C.; Sun, X. L.; Tang, Y. Org. Lett. 2006, 8, 2901–2904; (g) Cao, Y. J.; Lai, Y.
Y.; Wang, X.; Li, Y. J.; Xiao, W. J. Tetrahedron Lett. 2007, 48, 21–24.
12. (a) Hayashi, Y.; Gotoh, H.; Hayashi, T.; Shoji, M. Angew. Chem., Int. Ed. 2005, 44,
4212–4215; (b) Zu, L.; Li, H.; Wang, J.; Yu, X.; Wang, W. Tetrahedron Lett. 2006,
47, 5131–5134; (c) Li, Y.; Liu, X. Y.; Zhao, G. Tetrahedron: Asymmetry 2006, 17,
2034–2039; (d) Albertshofer, K.; Thayumanavan, R.; Utsumi, N.; Tanaka, F.;
4.3.12. (2R,3S)-3-(4-Methylphenyl)-2-methyl-4-nitrobutanal 4k
Compound 4k was prepared according to the general procedure
from propanal and trans-1-methyl-4-(2-nitrovinyl) benzene to
provide the title compound (78% yield) after flash column chroma-
tography on silica gel (petroleum ether/ethyl acetate = 10:1). 1H
NMR (400 MHz, CDCl3) d: 9.71 (s, 1H), 7.14 (d, 2H, J = 8.0 Hz),
7.05 (d, 2H, J = 8.0 Hz), 4.84–4.72 (m, 1H), 4.66 (dd, 1H, J = 3.2
and 12.6 Hz), 3.82–3.70 (m, 1H), 2.80–2.72 (m, 1H), 2.32 (s, 3H),
1.00 (d, 3H, J = 7.2 Hz). The enantiomeric excess was determined
by HPLC (Chiralcel OD-H), Hexane/i-PrOH 90:10, UV 254 nm,