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4.2.8. meso-1,2-Bis(2-bromophenyl)-1,2-ethanediamine 2h
White solid (2.76 g, 60% isolated yield). Rf (60% MeOH/EtOAc):
0.65; mp: 148–150 °C; IR (KBr):
max/cmꢁ13055, 2985, 1265 and
4.3.4. ( )-N-2-Amino-1,2-bis(4-bromophenyl)ethylallyl carba-
mate 4d
White solid (125 mg, 59% isolated yield). Rf (70% EtOAc/hexane):
0.41; mp: 124–126 °C; IR (KBr):
max/cmꢁ12940, 2269, 1707, 1645,
m
740; dH (300.13 MHz, CDCl3, Me4Si): 1.59 (br s, 4H), 4.72 (s, 2H),
7.09–7.16 (m, 2H), 7.28–7.44 (m, 4H), 7.49–7.55 (m, 2H); dC
(75.5 MHz, CDCl3, Me4Si): 59.5 (2CH), 125.1 (2C), 127.6 (2CH),
128.4 (2CH), 128.8 (2CH), 132.7 (2CH), 141.6 (2C); MS (ESI+, m/
z): 370.9 [(M+H)+, 100%] HRMS (ESI+, m/z) calcd for C14H15Br2N2
m
1545, 1451, 1254, 1160, 1026, 1000, 932, 831 and 795; dH
3
(300.13 MHz, MeOD, Me4Si): 4.29 (d, JHH = 8.6 Hz, 1H), 4.46–4.66
3
(m, 2H), 4.95 (d, JHH = 8.6 Hz, 1H), 5.19–5.36 (m, 2H), 5.85–6.05
(m, 1H), 7.35–7.56 (m, 4H), 7.59–7.77 (m, 4H); dC (75.5 MHz, MeOD,
Me4Si): 60.8 (CH), 62.4 (CH), 66.6 (CH2), 117.6 (CH2), 122.6–122.9
(2C), 130.0–131.0 (4CH), 132.7–132.9 (4CH), 134.5 (CH), 140.9 (C),
142.7 (C), 157.9 (C); MS (ESI+, m/z): 454.9 [(M+H)+, 100%]; HRMS
(ESI+, m/z) calcd for C18H19Br2N2O2 (M+H)+: 452.9822 found:
452.9822 (79Br,79Br), 454.9808 (79Br,81Br), 456.9787 (81Br,81Br).
(M+H)+: 368.9597 found: 368.9564
79Br,81Br), 372.9559 (81Br,81Br).
(
79Br,79Br), 370.9566
(
4.3. General procedure for the chemical synthesis of racemic
aminocarbamates 4a–h
4.3.5. ( )-N-2-Amino-1,2-bis(4-methylphenyl)ethylallyl carba-
mate 4e
To
(0.47 mmol) in dry CH2Cl2 (4.72 mL, 0.1 M), first DMAP (63.5,
0.52 mmol) and then allyl chloroformate (55 L, 0.52 mmol) were
added under a nitrogen atmosphere. The solution was stirred mag-
netically at room temperature until complete consumption of the
starting material (24 h, TLC analysis 60% MeOH/EtOAc). Next, the
solvent was distilled under reduced pressure, and the resulting
crude was purified by chromatography on silica gel (30-70%
EtOAc/hexane), to yield the corresponding racemic monocarba-
mate 4a–h as a white solid (29–75% isolated yield).
a solution of the corresponding meso-diamine 2a–h
White solid (44 mg, 29% isolated yield). Rf (70% EtOAc/hexane):
l
0.43; mp: 116–118 °C; IR (KBr): m
max/cmꢁ1 2800, 2150, 1702, 1542,
1490, 1252, 1153, 1090, 920, 816, and 737; dH (300.13 MHz, MeOD,
3
Me4Si): 2.52 (s, 6H), 4.24 (d, JHH = 8.7 Hz, 1H), 4.47–4.57 (m, 2H),
3
4.94 (d, JHH = 8.7 Hz, 1H), 5.18–5.32 (m, 2H), 5.84–6.03 (m, 1H),
7.27–7.41 (m, 8H); dC (75.5 MHz, MeOD, Me4Si): 21.5 (2CH3),
61.2 (CH), 62.8 (CH), 66.5 (CH2), 117.4 (CH2), 128.9–129.0 (4CH),
130.2–130.5 (4CH), 134.6 (CH), 138.5–138.9 (2C), 140.3 (C), 141.7
(C), 157.9 (C); MS (ESI+, m/z): 325.1 [(M+H)+, 100%]; HRMS (ESI+,
m/z) calcd for C20H25N2O2 (M+H)+: 325.1911 found: 325.1910.
4.3.1. ( )-N-(2-Amino-1,2-diphenylethyl)allyl carbamate 4a
White solid (109 mg, 75% isolated yield). Rf (70% EtOAc/hex-
ane): 0.40; mp: 115–117 °C; IR (KBr):
4.3.6. ( )-N-2-Amino-1,2-bis(3-methylphenyl)ethylallyl carba-
mate 4f
m
max/cmꢁ1 2936, 2269,
1694, 1604, 1572, 1446, 1266, 1159, 1090, 1026, 917 and 760; dH
White solid (70 mg, 46% isolated yield). Rf (70% EtOAc/hexane):
3
0.53; mp: 97–99 °C; IR (KBr): m
max/cmꢁ1 2924, 2490, 1697, 1536,
(300.13 MHz, MeOD, Me4Si): 4.31 (d, JHH = 8.7 Hz, 1H), 4.41–4.69
(m, 2H), 5.02 (br s, 1H), 5.13–5.31 (m, 2H), 5.82–6.01 (m, 1H),
7.38–7.65 (m, 10H); dC (75.5 MHz, MeOD, Me4Si): 61.2 (CH), 62.7
(CH), 66.2 (CH), 117.2 (CH2), 128.6 (2CH), 128.7 (2CH), 128.8
(2CH), 129.3 (2CH), 129.6 (2CH), 134.2 (CH), 141.5 (C), 143.1 (C),
157.6 (C): MS (ESI+, m/z): 297.1 [(M+H)+, 100%]; HRMS (ESI+, m/z)
calcd for C18H21N2O2 (M+H)+: 297.1598 found: 297.1584.
1495, 1451, 1251, 1042, 995, 922 and 785; dH (300.13 MHz, MeOD,
3
Me4Si): 2.52 (s, 6H), 4.23 (d, JHH = 8.8 Hz, 1H), 4.42–4.61 (m, 2H),
3
4.94 (d, JHH = 8.8 Hz, 1H), 5.16–5.32 (m, 2H), 5.83–6.00 (m, 1H),
7.21–7.47 (m, 8H); dC (75.5 MHz, MeOD, Me4Si); 21.8 (2CH3),
61.4 (CH), 63.0 (CH), 66.5 (CH2), 117.4 (CH2), 126.1 (2CH), 129.5–
129.8 (6CH), 134.6 (CH), 139.2 (C), 139.6 (C) 141.8 (C), 143.3 (C)
157.9 (C); MS (ESI+, m/z): 325.1 [(M+H)+, 100%]; HRMS (ESI+, m/z)
calcd for C20H25N2O2 (M+H)+: 325.1911 found: 325.1908.
4.3.2. ( )-N-2-Amino-1,2-bis(4-fluorophenyl)ethylallyl carba-
mate 4b
4.3.7. ( )-N-2-Amino-1,2-bis(3-bromophenyl)ethylallyl carba-
mate 4g
White solid (86 mg, 55% isolated yield,). Rf (70% EtOAc/hexane):
0.42; mp: 123–125 °C; IR (KBr): m
max/cmꢁ1 2936, 2269, 1695, 1603,
White solid (64 mg, 30% isolated yield). Rf (70% EtOAc/hexane):
1573, 1513, 1268, 1230, 1158, 923 and 841; dH (300.13 MHz,
0.57; mp: 188–191 °C; IR (KBr): m
max/cmꢁ1 3047, 2487, 1682, 1604,
3
MeOD, Me4Si): 4.28 (d, JHH = 8.6 Hz, 1H), 4.44–4.61 (m, 2H), 4.98
3
1554, 1454, 1251, 996,, 923 and 788; dH (300.13 MHz, MeOD,
(d, JHH = 8.6 Hz, 1H), 5.19–5.33 (m, 2H), 5.88–6.07 (m, 1H), 7.15–
3
Me4Si): 4.26 (d, JHH = 8.8 Hz, 1H), 4.44–4.64 (m, 2H), 4.93 (d,
7.38 (m, 4H), 7.49–7.64 (m, 4H); dC (75.5 MHz, MeOD, Me4Si):
3JHH = 8.8 Hz, 1H), 5.19–5.37 (m, 2H), 5.86–6.05 (m, 1H), 7.37–
7.85 (m, 8H); dC (75.5 MHz, MeOD, Me4Si): 60.9 (CH), 62.5 (CH),
66.7 (CH2), 117.7 (CH2), 123.6–123.8 (2C), 127.7–127.9 (2CH),
131.4–132.2 (6CH), 134.4 (CH), 142.3 (C), 146.1 (C), 157.8 (C);
MS (ESI+, m/z): 454.9 [(M+H)+, 100%]; HRMS (ESI+, m/z) calcd for
2
60.8 (CH), 62.4 (CH), 66.6 (CH2), 116.1–116.7 [ d, JCF = 22 Hz,
2CH)+(d, 2JCF = 22 Hz, 2CH)], 117.5 (CH2), 130.7–131.0 [(d, 3JCF = 8 -
3
Hz, 2CH)+(d, JCF = 8 Hz, 2CH)], 134.5 (CH), 137.8 (C), 139.5 (C),
1
1
157.9 (C) 163.9–164.0 [(d, JCF = 245 Hz, C)+(d, JCF = 245 Hz, C)];
MS (ESI+, m/z): 333.1 [(M+H)+, 100%]; HRMS (ESI+, m/z) calcd for
C
18H19Br2N2O2 (M+H)+: 452.9822 found: 452.9818 (79Br,79Br),
C
18H19F2N2O2 (M+H)+: 333.1409; found: 333.1381.
454.9805 (79Br,81Br), 456.9782 (81Br,81Br).
4.3.3. ( )-N-2-Amino-1,2-bis(4-chlorophenyl)ethylallyl carba-
mate 4c
4.3.8. ( )-N-2-Amino-1,2-bis(2-bromophenyl)ethylallyl carba-
mate 4h
White solid (92 mg, 54% isolated yield). Rf (70% EtOAc/hexane):
0.52; mp: 123–125 °C; IR (KBr): m
max/cmꢁ1 2900, 1694, 1536, 1491,
Yellow oil (129 mg, 61% isolated yield). Rf (70% EtOAc/hexane):
0.56; mp: 122–124 °C; IR (KBr): m
max/cmꢁ1 3005, 1703, 1504, 1468,
1410, 1250, 1090, 1012, 927 and 832; dH (300.13 MHz, CDCl3, Me4-
3
1454, 1241, 1023, 994, 931 and 737; dH (300.13 MHz, MeOD, Me4-
Si): 4.30 (d, JHH = 8.6 Hz, 1H), 4.47–4.63 (m, 2H), 4.97 (d,
3
3JHH = 8.6 Hz, 1H), 5.22–5.34 (m, 2H), 5.87–6.03 (m, 1H), 7.44–
7.59 (m, 8H); dC (75.5 MHz, CDCl3, Me4Si): 60.7 (CH), 62.3 (CH),
66.6 (CH2), 117.6 (CH2), 129.7–129.9 (4CH), 130.6–130.7 (4CH),
134.5–134.8 (2C+CH), 140.4 (C), 142.3 (C) 157.9 (C); MS (ESI+, m/
z): 365.0 [(M+H)+, 100%]; HRMS (ESI+, m/z) calcd for C18H19Cl2N2O2
(M+H)+: 365.0818 found: 365.0812 (35Cl,35Cl), 367.0782 (35Cl,37Cl).
Si): 4.54–4.69 (m, 2H), 4.96 (d, JHH = 6.4 Hz, 1H), 5.23–5.43 (m,
3
2H), 5.80 (d, JHH = 6.4 Hz, 1H), 5.92–6.11 (m, 1H), 7.29–7.74 (m,
8H); dC (75.5 MHz, MeOD, Me4Si): 59.3 (CH), 59.5 (CH), 66.8
(CH2), 117.9 (CH2), 126.2–126.4 (2C), 129.0–129.1 (2CH), 130.0–
130.6 (4CH), 134.1–134.2 (2CH), 134.5 (CH) 139.9 (C), 141.8 (C),
157.9 (C); MS (ESI+, m/z): 454.9 [(M+H)+, 100%]; HRMS (ESI+, m/z)