Page 5 of 9
The Journal of Organic Chemistry
tert-butyl phenethylcarbamate (2f, Table 2, entry 6).21 Oil (54
tert-butyl (2-iodophenyl)carbamate (2o, Table 2, entry 15).28
Orange oil (86 mg, 90% yield); Rf = 0.49 (hexane:EtOAc =
20:1); 1H NMR (400 MHz, CDCl3): δ 8.05 (dd, J = 8.3, 1.0 Hz,
1H), 7.74 (dd, J = 7.9, 1.4 Hz, 1H), 7.36-7.27 (m, 1H), 6.83 (s,
1H), 6.78-6.71 (m, 1H), 1.54 (s, 9H); 13C NMR (101 MHz,
CDCl3): δ 152.5, 138.8, 129.1, 124.6, 120.1, 88.7, 81.0, 28.3.
tert-butyl (2-bromophenyl)carbamate (2p, Table 2, entry 16).29
Colorless oil (73 mg, 89% yield); Rf = 0.48 (hexane:EtOAc =
20:1); 1H NMR (400 MHz, CDCl3): δ 8.17 (dd, J = 8.3, 1.1 Hz,
1H), 7.51 (dd, J = 8.0, 1.5 Hz, 1H), 7.33-7.23 (m, 1H), 7.03 (s,
1H), 6.93-6.89 (m, 1H), 1.56 (s, 9H); 13C NMR (101 MHz,
CDCl3): δ 152.3, 136.3, 132.2, 128.2, 123.8, 120.0, 112.3, 81.0,
28.2.
tert-butyl (2-(trifluoromethyl)phenyl)carbamate (2q, Table 2,
entry 17).30 Colorless oil (55 mg, 70% yield); Rf = 0.51
(hexane:EtOAc = 20:1);1H NMR (400 MHz, CDCl3): δ 8.14 (d,
J = 8.4 Hz, 1H), 7.56 (d, J = 7.9 Hz, 1H), 7.52 (t, J = 7.9 Hz,
1H), 7.13 (t, J = 7.7 Hz, 1H), 6.80 (s, 1H), 1.53 (s, 9H); 13C
NMR (101 MHz, CDCl3); δ 152.5, 136.2, 132.8, 125.9
(q, J = 5.4), 124.1 (q, J = 273.8), 123.0, 122.3, 118.9
(q, J = 29.7), 81.3, 28.2.
mg, 81% yield); Rf = 0.42 (hexane:EtOAc = 20:1); 1H NMR
(700 MHz, CDCl3): δ 7.31 (t, J = 7.7 Hz, 2H), 7.22 (t, J = 7.0
Hz, 1H), 7.20 (d, J = 7.7 Hz, 2H), 4.56 (s, 1H), 3.39 (d, J = 6.3
Hz, 2H), 2.80 (t, J = 7.0 Hz, 2H), 1.44 (s, 9H); 13C NMR (175
MHz, CDCl3): δ 155.8, 139.0, 128.8, 128.5, 126.4, 79.2, 41.7,
36.2, 28.4.
1
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3
4
5
6
7
8
tert-butyl (3-phenylpropyl)carbamate (2g, Table 2, entry 7).22
White solid (60 mg, 85% yield); mp: 36-37 °C ; Rf = 0.42
1
(hexane:EtOAc = 20:1); H NMR (400 MHz, CDCl3): δ 7.29-
9
7.26 (m, 2H), 7.20-7.16 (m, 3H), 4.54 (s, 1H), 3.15 (d, J = 6.4
Hz, 2H), 2.64 (t, J = 7.6 Hz, 2H), 1.85-1.77 (m, 2H), 1.45 (s,
9H); 13C NMR (101 MHz, CDCl3): δ 156.0, 141.6, 128.4, 128.4,
125.9, 79.1, 40.2, 33.1, 31.8, 28.4.
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18
19
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28
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60
tert-butyl (4-phenylbutyl)carbamate (2h, Table 2, entry 8).23 Oil
(64 mg, 86% yield); Rf = 0.43 (hexane:EtOAc = 20:1); 1H NMR
(400 MHz, CDCl3): δ 7.27 (t, J = 8.0 Hz, 2H), 7.17 (t, J = 6.8
Hz, 3H), 4.52 (s, 1H), 3.13 (d, J = 6.4 Hz, 2H), 2.62 (t, J = 7.6
Hz, 2H), 1.66-1.60 (m, 2H), 1.54-1.44 (m, 2H), 1.44 (s, 9H);
13C NMR (101 MHz, CDCl3): δ 155.9, 142.1, 128.3, 128.2,
125.7, 79.0, 40.4, 35.4, 28.6, 28.5, 28.4.
tert-butyl (2,2-diphenylethyl)carbamate (2i, Table 2, entry 9).
White solid (68 mg, 76% yield); mp: 87-88 °C; Rf = 0.36
(hexane:EtOAc = 20:1); IR (film) 3358, 2969, 1712, 1503, 1247,
tert-butyl o-tolylcarbamate (2r, Table 2, entry 18).31 White
solid (55 mg, 70% yield); mp: 83-84 oC; Rf = 0.55
(hexane:EtOAc = 20:1); 1H NMR (400 MHz, CDCl3): δ 7.81 (d,
J = 7.8 Hz, 1H), 7.23-7.08 (m, 2H), 6.98 (t, J = 7.2 Hz, 1H),
6.30 (brs, 1H), 2.25 (s, 3H), 1.54 (s, 9H); 13C NMR (101 MHz,
CDCl3): δ 153.0, 136.3, 130.2, 127.3, 126.7, 123.6, 120.9, 80.3,
28.3, 17.6.
1
1168, 697 cm-1; H NMR (400 MHz, CDCl3): δ 7.31-7.18 (m,
10H), 4.52 (brs, 1H), 4.16 (t, J = 7.6 Hz, 1H), 3.76 (t, J = 6.4
Hz, 2H), 1.40 (s, 9H); 13C NMR (101 MHz, CDCl3): δ 155.7,
141.9, 128.6, 128.0, 126.7, 79.2, 51.0, 44.9, 28.3; HRMS (ESI-
TOF) m/z: [M + H]+ Calcd for C19H24NO2 298.1802; found
298.1805.
tert-butyl phenylcarbamate (2s, Table 2, entry 19).32 White
solid (41 mg, 71% yield); mp: 135-136 oC; Rf = 0.57
(hexane:EtOAc = 20:1); 1H NMR (400 MHz, CDCl3): δ 7.37 (d,
J = 7.9 Hz, 2H), 7.32-7.26 (m, 2H), 7.08-6.96 (m, 1H), 6.60 (s,
1H), 1.53 (s, 9H); 13C NMR (101 MHz, CDCl3): δ 152.8, 138.3,
128.9, 122.9, 118.5, 80.4, 28.3.
tert-butyl (2,2,2-triphenylethyl)carbamate (2j, Table 2, entry
10). White solid (82 mg, 73% yield); mp: 57-59 °C; Rf = 0.34
(hexane:EtOAc = 20:1); IR (film) 2972, 1760, 1244, 694 cm-1;
1H NMR (400 MHz, CDCl3): δ 7.30-7.22 (m, 15H), 4.34 (s, 3H),
1.37 (s, 9H); 13C NMR (101 MHz, CDCl3): δ 155.6, 145.2,
129.1, 128.2, 126.5, 79.4, 56.9, 48.9, 28.3; HRMS (ESI-TOF)
m/z: [M + H]+ Calcd for C25H28NO2 374.2120; found 374.2124.
tert-butyl (2-(methylthio)ethyl)carbamate (2k, Table 2, entry
11).24 Oil (35 mg, 61% yield); Rf = 0.49 (hexane:EtOAc = 20:1);
1H NMR (400 MHz, CDCl3): δ 4.92 (s, 1H), 3.32 (d, J = 6.0 Hz,
2H), 2.61 (t, J = 6.4 Hz, 2H), 2.10 (s, 3H), 1.43 (s, 9H); 13C
NMR (101 MHz, CDCl3): δ 155.8, 79.4, 39.0, 34.2, 28.4, 15.0.
tert-butyl (4-phenylpent-4-en-1-yl)carbamate (2l, Table 2,
entry 12).25 Oil (50 mg, 64% yield); Rf = 0.39 (hexane:EtOAc =
20:1); 1H NMR (400 MHz, CDCl3): δ 7.38 (d, J = 7.2 Hz, 2H),
7.32 (t, J = 7.6 Hz, 2H), 7.28-7.24 (m, 1H), 5.28 (s, 1H), 5.08
(s, 1H), 4.51 (brs, 1H), 3.14 (d, J = 6.0 Hz, 2H), 2.54 (t, J = 7.6
Hz, 2H), 1.67-1.60 (m, 2H), 1.43 (s, 9H); 13C NMR (101 MHz,
CDCl3): δ 155.9, 147.6, 140.9, 128.3, 127.4, 126.1, 112.7, 79.0,
40.2, 32.5, 28.5, 28.4.
tert-butyl (2-nitrophenyl)carbamate (2t, Table 2, entry 20).33
o
Yellow solid (52 mg, 73% yield); mp: 89-90 C; Rf = 0.48
(hexane:EtOAc = 10:1); 1H NMR (400 MHz, CDCl3): δ 9.64
(s, 1H), 8.55 (dd, J = 8.6, 1.0 Hz, 1H), 8.17 (dd, J = 8.5, 1.5 Hz,
1H), 7.65-7.52 (m, 1H), 7.07 (ddd, J = 8.4, 7.4, 1.2 Hz, 1H),
1.54 (s, 9H); 13C NMR (101 MHz, CDCl3): δ 152.1, 135.9,
135.7, 125.8, 121.8, 120.6, 81.8, 28.2.
tert-butyl (2-cyanophenyl)carbamate (2v, Table 2, entry 22).34
Oil (20 mg, 32% yield); Rf = 0.51 (hexane:EtOAc = 10:1); 1H
NMR (400 MHz, CDCl3) δ 8.23 (d, J = 8.4 Hz, 1H), 7.55 (t, J
= 8.6 Hz, 2H), 7.08 (t, J = 7.6 Hz, 1H), 7.02 (s, 1H), 1.53 (s,
12H); 13C NMR (101 MHz, CDCl3) δ 151.8, 141.4, 134.1, 132.2,
122.7, 119.1, 116.5, 100.6, 81.9, 28.2.
tert-butyl furan-2-ylcarbamate (2w, Table 2, entry 23).35 White
solid (28 mg, 51% yield); mp: 90-92°C; Rf
= 0.41
(hexane:EtOAc = 10:1); 1H NMR (400 MHz, CDCl3) δ 7.06 (s,
1H), 6.57 (s, 1H), 6.34 (s, 1H), 6.03 (s, 1H), 1.50 (s, 9H); 13C
NMR (101 MHz, CDCl3) δ 151.8, 145.3, 136.1, 111.3, 95.2,
81.3, 28.2.
tert-butyl-styrylcarbamate (2m, Table 2, entry 13).26 White
solid (43 mg, 65% yield); mp: 117-119 oC; 1H NMR (400 MHz,
CDCl3): δ 7.26-7.18 (m, 5H), 7.16-7.11 (m, 1H), 6.46 (d, J =
7.2 Hz, 1H), 5.89 (d, J = 14.4 Hz, 1H), 1.49 (s, 9H); 13C NMR
(101 MHz, CDCl3): δ 152.7, 136.5, 128.5, 125.9, 125.1, 124.3,
109.6, 80.7, 28.2.
tert-butyl thiophen-2-ylcarbamate (2x, Table 2, entry 24).36
White solid (35 mg, 58% yield); mp: 155-156 °C; Rf = 0.36
(hexane:EtOAc = 10:1);1H NMR (400 MHz, CDCl3) δ 6.93 (brs,
1H), 6.83-6.79 (m, 2H), 6.53-6.52 (m, 1H), 1.52 (s, 9H); 13C
NMR (75 MHz, CDCl3) δ 152.4, 139.9, 124.2, 116.8, 111.1,
84.5, 28.0.
benzyl phenethylcarbamate (2n, Table 2, entry 14).27 White
solid (60 mg, 79% yield); mp: 61-63°C; Rf
= 0.29
1
(hexane:EtOAc = 20:1); H NMR (400 MHz, CDCl3): δ 7.26-
7.09 (m, 10H), 5.01 (s, 2H), 4.77 (s, 1H), 3.40-3.35 (m, 2H),
2.73 (t, J = 7.2 Hz, 2H); 13C NMR (101 MHz, CDCl3): δ 156.2,
138.6, 136.5, 128.7, 128.5, 128.4, 128.0, 126.4, 66.5, 42.1, 36.0.
tert-butyl cyclobutylcarbamate (2y, Table 3, entry 1).37 White
solid (26 mg, 51% yield); mp: 72-73 °C; Rf = 0.39
(hexane:EtOAc = 20:1); 1H NMR (400 MHz, CDCl3): δ 4.70 (s,
1H), 4.10-4.08 (m, 1H), 2.29-2.27 (m, 2H), 1.84-1.74 (m, 2H),
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