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Z. Chunhong et al. / Tetrahedron: Asymmetry 25 (2014) 278–283
4.2.7. (1R,2R)-N1,N2-Didodecylcyclohexane-1,2-diamine di-
hydrochloride 1gꢀ2HCl
(D2O, 75 MHz) d: 22.35, 23.09, 24.37, 24.71, 25.02, 25.59, 26.70,
26.81, 28.42, 28.57, 45.05, 45.10, 53.91, 53.99, 54.09, 54.17,
According to the general procedure, 1gꢀ2HCl was obtained as a
57.06, 57.43. IR: = 3427, 2958, 2871, 2694, 1590, 1471, 1391,
m
white solid. Yield: 59%. ½a D25
ꢃ
¼ ꢁ31:0 (c 0.57, MeOH). 1H NMR
1043, 999 cmꢁ1 HRMS (ESI): Calcd for C18H39N2 [M+H]+
.
(300 MHz, D2O, 25 °C) d: 0.86–0.90 (m, 6H, CH2CH3), 1.25–1.33
(m, 40H, CH2CH3), 1.88–2.09 (m, 8H, CH2 of DACH), 3.01–3.13 (m,
2H, NHCH), 3.86 (m, 4H, NHCH2). 13C NMR (CDCl3, 75 MHz) d:
14.06, 22.65, 23.13, 26.18, 29.12, 29.31, 29.54, 29.61, 31.88,
283.3108, Found: 283.3117.
4.2.13. (1R,2R)-N1,N2-Bis(5-methylhexan-2-yl)cyclohexane-1,2-
diamine dihydrochloride 1mꢀ2HCl
45.34, 57.41, 76.58, 77.00, 77.43. IR:
m
.
= 3349, 2921, 2850, 2389,
HRMS (ESI): Calcd for
According to the general procedure, 1mꢀ2HCl was obtained as a
1578, 1473, 1372, 1015, 728 cmꢁ1
white solid. Yield: 81%. ½a D25
ꢃ
¼ ꢁ70:6 (c 0.52, H2O). 1H NMR
C
30H63N2 [M+H]+ 451.4986, Found: 451.4970.
(300 MHz, D2O, 25 °C) d: 0.88 (d, J = 6.5 Hz, 12H, CHCH3), 1.24–
1.38 (m, 6H, NHCHCH3), 1.43–1.61 (m, 2H, CHCH3), 1.65–2.30 (m,
16H, CH2CH and CH2 of DACH), 3.53 (s, 4H, NHCH). 13C NMR
(D2O, 75 MHz) d: 17.09, 19.32, 24.24, 24.33, 24.47, 24.66, 28.38,
28.58, 29.75, 29.89, 31.12, 31.24, 34.04, 34.09, 36.00, 36.30,
4.2.8. (1R,2R)-N1,N2-Di-(2-butyl) cyclohexane-1,2-diamine di-
hydrochloride 1hꢀ2HCl
According to the general procedure, 1hꢀ2HCl was obtained as a
white solid. Yield: 66%. ½a D25
ꢃ
¼ ꢁ71:4 (c 0.51, H2O). 1H NMR
55.66, 55.69, 57.19, 57.43. IR:
m = 3404, 2954, 2869, 1589, 1468,
(300 MHz, D2O, 25 °C) d: 0.96 (t, J = 7.5 Hz, 6H, CH2CH3), 1.02–
1.41 (m, 6H, NHCHCH3), 1.47–2.31 (m, 12H, CH2CH3, CH2 of DACH),
3.49–3.57 (m, 4H, NHCH). 13C NMR (D2O, 75 MHz) d: 24.95, 25.08,
26.19, 26.25, 28.39, 28.64, 29.32, 29.44, 31.96, 32.13, 54.34, 54.38,
1389, 1064 cmꢁ1 HRMS (ESI): Calcd for C20H43N2 [M+H]+
.
311.3421, Found: 311.3419.
4.2.14. (1R,2R)-N1,N2-Bis(3,5,5-trimethylhexyl)cyclohexane-1,2-
diamine dihydrochloride 1nꢀ2HCl
56.41, 56.44. IR:
m = 3429, 2944, 2818, 1583, 1456, 1393, 1026,
998 cmꢁ1. HRMS (ESI): Calcd for C14H31N2 [M+H]+ 227.2482,
Found: 227.2484.
According to the general procedure, 1nꢀ2HCl was obtained as a
white solid. Yield: 86%. ½a D25
ꢃ
¼ ꢁ37:8 (c 0.49, H2O). 1H NMR
(300 MHz, D2O, 25 °C) d: 0.92 (d, 24H, CHCH3 and C(CH3)3), 1.10–
1.24 (m, 2H, CHCH3), 1.40–2.29 (m, 16H, CHCH2 and CH2 of DACH),
3.05 (m, 2H, NHCH), 3.27–3.45 (m, 4H, NHCH2). 13C NMR (D2O,
75 MHz) d: 24.01, 24.25, 28.23, 29.36, 29.46, 31.77, 32.72, 37.23,
4.2.9. (1R,2R)-N1,N2-Di(2-pentanyl)cyclohexane-1,2-diamine di-
hydrochloride 1iꢀ2HCl
According to the general procedure, 1iꢀ2HCl was obtained as a
white solid. Yield: 79%. ½a D25
ꢃ
¼ ꢁ82:3 (c 0.53, H2O). 1H NMR
46.97, 52.59, 52.77, 59.80. IR: m = 3406, 2954, 2867, 2703, 1587,
(300 MHz, D2O, 25 °C) d: 0.93 (t, J = 7.2 Hz, 6H, CH2CH3), 1.34 (d,
J = 6.3 Hz, 6H, CHCH3), 1.43–2.31 (m, 16H, CH2CH3 and CH2 of
DACH), 3.38–3.58 (m, 4H, NHCH). 13C NMR (D2O, 75 MHz) d:
15.49, 16.90, 19.06, 19.23, 20.49, 20.78, 24.34, 24.95, 28.57,
1465, 1393, 1364, 1015 cmꢁ1. HRMS (ESI): Calcd for C24H51N2
[M+H]+ 367.4047, Found: 367.4039.
4.3. General procedure for the catalytic Henry reaction
28.62, 35.17, 38.22, 55.12, 55.17, 57.18, 57.47. IR:
m = 3433, 2822,
2391, 1582, 1456, 1391, 1025, 994, 744 cmꢁ1. HRMS (ESI): Calcd
for C16H35N2 [M+H]+ 255.2975, Found: 255.2800.
Ligand 1n (0.6 mmol, 12 mol %) and Cu(OAc)2ꢀH2O (10 mg,
0.5 mmol, 10 mol %) were added with i-PrOH (1.0 mL) to a test
tube, to give a deep blue solution after being slightly heated for
30 s and stirred for 1.0 h at 20 °C. Next, a solution of the corre-
sponding aldehyde (0.5 mmol, 1.0 equiv) in i-PrOH (0.3 mL) was
added, the reaction mixture was cooled to ꢁ20 °C, and stirred for
15 min. To the resulting solution was successively added nitroal-
kane (5.0 mmol, 10 equiv), and DIPEA (7.7 mol %, 5 mg), and the
tube was put in a cooling circulation pump at the ꢁ20 °C. After
48 h, the mixture was purified by column chromatography on sil-
ica gel (30 g, PE/AcOEt, 4:1, v/v), to give the corresponding product.
HPLC was used to determine the enantiomeric excess by Chiralpak
IC, Chiracel OD-H, Chiralpak AD-H, or Chiralpak AS-H chiral
columns.
4.2.10. (1R,2R)-N1,N2-Di(2-hexanyl)cyclohexane-1,2-diamine di-
hydrochloride 1jꢀ2HCl
According to the general procedure, 1jꢀ2HCl was obtained as a
white solid. Yield: 65%. ½a D25
ꢃ
¼ ꢁ67:2 (c 0.58, H2O). 1H NMR
(300 MHz, D2O, 25 °C) d: 0.89 (t, J = 6.4 Hz, 6H, CH2CH3), 1.30–
1.39 (m, 6H, CHCH3), 1.53–2.30 (m, 20H, CH2CH3 and CH2 of DACH),
3.55 (m, 4H, NHCH). 13C NMR (D2O, 75 MHz) d: 15.73, 16.97, 17.03,
19.29, 24.26, 24.37, 24.48, 24.66, 28.39, 28.58, 29.15, 29.43, 35.80,
35.84, 55.38, 55.46, 57.18, 57.44. IR:
m = 3406, 2955, 2787, 1589,
1467, 1391, 1041, 732 cmꢁ1. HRMS (ESI): Calcd for C18H39N2
[M+H]+ 283.3108, Found: 283.3085.
(1S)-2-Nitro-1-phenylethanol 3a: Chiralpak IC, n-hexane/i-PrOH,
90:10, 0.8 mL/min, k = 220 nm, tminor = 13.5 min, tmajor = 14.4 min.
(1S)-1-Nitrobutan-2-ol 3b: Chiralpak AD-H, n-hexane/i-PrOH,
90:10, 0.5 mL/min, k = 210 nm, tminor = 35.7 min, tmajor = 54.1 min.
(1S)-1-Nitropentan-2-ol 3c: Chiralpak AS-H, n-hexane/i-PrOH,
95:5, 0.8 mL/min, k = 220 nm, tminor = 35.2 min, tmajor = 39.7 min.
(1S)-3-Methyl-1-nitrobutan-2-ol 3d: Chiracel OD-H, n-hexane/
4.2.11. (1R,2R)-N1,N2-Di(3-pentanyl)cyclohexane-1,2-diamine di-
hydrochloride 1kꢀ2HCl
According to the general procedure, 1kꢀ2HCl was obtained as a
white solid. Yield: 43%. ½a D25
ꢃ
¼ ꢁ80:1 (c 0.47, H2O). 1H NMR
(300 MHz, D2O, 25 °C) d: 0.92–1.01 (m, 12H, CH2CH3), 1.39–2.37
(m, 16H, CH2CH3 and CH2 of DACH), 3.47–3.54 (m, 4H, NHCH).
13C NMR (D2O, 75 MHz) d: 10.39, 11.06, 22.83, 24.62, 25.55,
i-PrOH,
98:2,
0.5 mL/min,
k = 210 nm,
tminor = 30.3 min,
28.77, 57.86, 61.31. IR:
m = 3432, 2966, 2835, 1571, 1461, 1389,
tmajor = 34.7 min.
943 cmꢁ1. HRMS (ESI): Calcd for C16H35N2 [M+H]+ 255.2795,
Found: 255.2778.
(1S)-1-Nitrohexan-2-ol 3e: Chiracel OD-H, n-hexane/i-PrOH,
98:2, 0.5 mL/min, k = 210 nm, tminor = 41.4 min, tmajor = 43.2 min.
(1S)-4-Methyl-1-nitropentan-2-ol 3f: Chiralpak AD-H, n-hexane/
4.2.12. (1R,2R)-N1,N2-Bis(4-methylpentan-2-yl)cyclohexane-1,2-
diamine dihydrochloride 1lꢀ2HCl
i-PrOH,
95:5,
0.5 mL/min,
k = 210 nm,
tminor = 25.4 min,
tmajor = 36.2 min.
According to the general procedure, 1lꢀ2HCl was obtained as a
(1S)-3,3-Dimethyl-1-nitrobutan-2-ol 3g: Chiralpak AD-H, n-hex-
ane/i-PrOH, 95:5, 0.5 mL/min, k = 210 nm, tminor = 14.2 min,
tmajor = 14.6 min.
(1S)-1-Nitroheptan-2-ol 3h: Chiralpak AD-H, n-hexane/i-PrOH,
95:5, 0.5 mL/min, k = 210 nm, tminor = 30.4 min, tmajor = 43.7 min.
white solid. Yield: 47%. ½a D25
ꢃ
¼ ꢁ69:8 (c 0.5, H2O). 1H NMR
(300 MHz, D2O, 25 °C) d: 0.88–0.97 (m, 12H, CHCH3), 1.30–1.39
(m, 6H, NHCHCH3), 1.43–1.61 (m, 2H, CHCH3), 1.72–2.37 (m, 12H,
CHCH2 and CH2 of DACH), 3.57–3.62 (m, 4H, NHCH). 13C NMR