Y. Feng et al. / Tetrahedron 74 (2018) 2669e2676
2675
13C NMR (125 MHz, CDCl3)
125.86, 125.55, 124.2, 124.1, 115.0, 113.7, 58.5, 56.8, 38.7, 30.3, 24.1.
HRMS (ESI-TOF) m/z: [MþH]þ for C16H17N2S 269.1107, found
269.1116.
d
145.1, 135.0, 130.3, 128.4, 126.2, 125.9,
4.3. General procedure for the cyclization of 2-allylaniline
compounds with NaSCN
To a round-bottom flask was charged with compunds
1
(0.5 mmol), EtOAc (4 mL) NaSCN (1.5 mmol) and I2 (1.75 mmol)
successively. Then the resulting mixture was stirred under open-
flask conditions at 70 ꢀC (oil bath temperature) for 8 h. The reac-
tion was quenched with saturated solution of Na2S2O3. The organic
phase was separated, and the aqueous layer was extracted with
EtOAc (5 ꢃ 3 mL). The combined organic solution was dried with
Mg2SO4 and concentrated in vacuo. The residue was purified by a
column chromatography to give the corresponding products 5 in
yields as listed in Table 4.
4.2.15. 2-Methyl-1-phenyl-5-(thiocyanatomethyl)pyrrolidine (3p)
White solid; 83% yield, 96 mg; mp 66e67 ꢀC. 1H NMR (500 MHz,
CDCl3)
d
7.26e7.23 (m, 2H), 6.72 (t, J ¼ 7.0 Hz,1H), 6.63 (d, J ¼ 8.0 Hz,
2H), 4.21 (t, J ¼ 8.0 Hz, 1H), 4.14e4.09 (m, 1H), 3.27 (d, J ¼ 13.5 Hz,
1H), 2.61 (dd, J ¼ 22.5, 9.5 Hz,1H), 2.38e2.30 (m, 1H), 2.22e2.14 (m,
1H), 2.04 (dd, J ¼ 12.5, 7.0 Hz, 1H), 1.75 (dd, J ¼ 12.5, 7.0 Hz, 1H), 1.25
(d, J ¼ 11.0 Hz, 3H), 13C NMR (125 MHz, CDCl3)
d 144.0, 129.8, 116.9,
113.9, 112.3, 57.5, 53.6, 34.4, 30.3, 27.4, 18.0. HRMS (ESI-TOF) m/z:
[MþH]þ for C13H17N2S 233.1107, found 233.1108.
4.3.1. 1-Ethyl-2-(thiocyanatomethyl)indoline (5a)
Brown oil; 42% yield, 46 mg. 1H NMR (500 MHz, CDCl3)
4.2.16. 1,4,4-Triphenyl-2-(thiocyanatomethyl)pyrrolidine (3q)
White solid; 21% yield, 39 mg; mp 177e183 ꢀC. 1H NMR
(500 MHz, CDCl3) d 7.35e7.33 (m, 3H), 7.31e7.25 (m, 5H), 7.25e7.20
d
7.11e7.10 (m, 2H), 6.72 (t, J ¼ 7.5 Hz, 1H), 6.50 (d, J ¼ 8.0 Hz, 1H),
4.08e4.03 (m, 1H), 3.37e3.28 (m, 4H), 3.18e3.10 (m, 1H), 2.96 (dd,
J ¼ 16.0, 8.0 Hz, 1H), 1.14 (t, J ¼ 7.0 Hz, 3H). 13C NMR (125 MHz,
(m, 4H), 7.06 (d, J ¼ 7.5 Hz, 2H), 6.97 (t, J ¼ 6.5 Hz, 1H), 4.30 (d,
J ¼ 12.5 Hz, 1H), 3.99 (d, J ¼ 11.0 Hz, 1H), 3.31 (t, J ¼ 10.5 Hz, 1H),
3.31e3.28 (m, 3H), 2.55 (t, J ¼ 12.5 Hz, 1H), 13C NMR (125 MHz,
CDCl3) d 150.5, 128.0, 127.9, 124.7, 119.0, 112.8, 108.3, 61.4, 41.4, 38.3,
34.3, 11.2. HRMS (ESI-TOF) m/z: [MþH]þ for C12H15N2S 219.0951,
found 219.0959.
CDCl3)
d 150.5, 146.5, 144.6, 129.6, 128.8, 128.7, 128.4, 127.0, 126.8,
126.6, 121.4, 117.7, 110.4, 58.8, 56.5, 48.2, 42.4, 41.9. HRMS (ESI-TOF)
4.3.2. 1-Benzyl-2-(thiocyanatomethyl)indoline (5b)
m/z: [MþH]þ for C24H23N2S 371.1577, found 371.1594.
White oil; 52% yield, 72 mg. 1H NMR (500 MHz, CDCl3)
d
7.35e7.27 (m, 5H), 7.10 (t, J ¼ 7.0 Hz, 1H), 7.06 (t, J ¼ 7.5 Hz, 1H),
4.2.17. 1-Benzyl-4,4-diphenyl-2-(thiocyanatomethyl)pyrrolidine
(3r)
6.73 (t, J ¼ 7.5 Hz, 1H), 6.46 (d, J ¼ 8.0 Hz, 1H), 4.38 (d, J ¼ 16.0 Hz,
1H), 4.30 (d, J ¼ 16.0 Hz, 1H), 4.06e4.00 (m, 1H), 3.36 (dd, J ¼ 16.0,
White solid; 24% yield, 46 mg; mp 156e159 ꢀC. 1H NMR
9.5 Hz, 1H), 3.18 (d, J ¼ 5.0 Hz, 2H), 3.01 (dd, J ¼ 16.0, 8.5, Hz,1H). 13
C
(500 MHz, CDCl3)
d
7.35e7.34 (m, 2H), 7.31e7.29 (m, 7H), 7.23e7.22
NMR (125 MHz, CDCl3) d 151.9, 138.0, 129.0, 128.1, 127.7, 127.6, 127.4,
(m, 2H), 7.19e7.15 (m, 2H), 7.09 (d, J ¼ 6.5 Hz, 2H), 3.65e3.56 (m,
3H), 3.21 (d, J ¼ 6.5 Hz, 1H), 3.14 (t, J ¼ 10.5 Hz, 1H), 2.92 (d,
J ¼ 12.5 Hz, 1H), 2.42 (t, J ¼ 12.0, 1H), 2.37e2.31 (m, 2H). 13C NMR
124.7, 119.1, 112.7, 108.1, 63.4, 52.6, 38.4, 34.4. HRMS (ESI-TOF) m/z:
[MþH]þ for C17H17N2S 281.1107, found 218.1104.
(125 MHz, CDCl3)
d
146.9, 144.6, 137.4, 129.4, 128.64, 128.58, 128.55,
4.3.3. 1-(Furan-2-ylmethyl)-2-(thiocyanatomethyl)indoline (5c)
White solid; 33% yield, 45 mg; mp 59e62 ꢀC. 1H NMR (500 MHz,
128.4,127.7, 126.7, 126.6,126.3, 110.6, 62.7, 61.8, 59.2, 48.1, 42.7, 41.8.
HRMS (ESI-TOF) m/z: [MþH]þ for C25H25N2S 385.1733, found
385.1738.
CDCl3)
d
7.35 (s, 1H), 7.12 (t, J ¼ 7.5 Hz, 1H), 6.99 (d, J ¼ 7.5 Hz, 1H),
6.81 (d, J ¼ 8.0 Hz, 1H), 6.72 (t, J ¼ 7.5 Hz, 1H), 6.30 (s, 1H), 6.22 (s,
1H), 4.50 (d, J ¼ 16.5 Hz, 1H), 4.40 (d, J ¼ 16.5 Hz, 1H), 3.93 (d,
J ¼ 6.0 Hz, 1H), 3.73 (d, J ¼ 12.0 Hz, 1H), 3.50 (dd, J ¼ 12.0, 6.5 Hz,
4.2.18. 1-Phenyl-2-(thiocyanatomethyl)piperidine (3s)
1H), 3.32 (dd, J ¼ 16.5, 4.5 Hz, 1H), 3.05 (dd, J ¼ 16.5, 6.5 Hz, 1H). 13
C
Brown oil; 42% yield, 49 mg; 1H NMR (500 MHz, CDCl3)
d 7.28 (t,
NMR (125 MHz, CDCl3)
d 151.2, 143.5, 142.4, 130.0, 128.2, 118.4,
J ¼ 8.5 Hz, 2H), 6.97 (d, J ¼ 8.0 Hz, 2H), 6.91 (t, J ¼ 7.0 Hz, 1H),
4.06e4.02 (m, 1H), 3.32e3.28 (m, 1H), 3.20e3.16 (m, 1H), 3.04 (dd,
J ¼ 12.5, 9.0 Hz, 1H), 3.00e2.94 (m, 1H), 1.93e1.88 (m, 2H),
118.3, 112.3,111.8, 110.5, 108.2, 53.5, 48.1, 43.2, 34.4. HRMS (ESI-TOF)
m/z: [MþH]þ for C15H15N2OS 271.0900, found 271.0904.
1.74e1.60 (m, 4H). 13C NMR (125 MHz, CDCl3)
d 150.1, 129.6, 120.9,
4.3.4. 1-(Naphthalen-1-ylmethyl)-2-(thiocyanatomethyl)indoline
(5d)
118.2, 112.8, 56.1, 46.0, 33.6, 27.0, 25.2, 19.8. HRMS (ESI-TOF) m/z:
[MþH]þ for C13H17N2S 233.1107, found 233.1101.
Light yellow solid; 30% yield, 50 mg; mp 125e138 ꢀC. 1H NMR
(500 MHz, CDCl3)
d
7.88 (dd, J ¼ 25.5, 5.5 Hz, 2H), 7.80 (d, J ¼ 8.0 Hz,
4.2.19. 2-(Thiocyanatomethyl)-1-(p-tolyl)piperidine (3t)
1H), 7.54 (d, J ¼ 4.5 Hz, 2H), 7.43e7.38 (m, 2H), 7.06 (s, 2H), 6.74 (t,
J ¼ 7.0 Hz, 1H), 6.61 (d, J ¼ 15.0 Hz, 1H), 4.94 (q, J ¼ 16.5 Hz, 2H), 3.97
(s, 1H), 3.74 (d, J ¼ 12.5 Hz, 1H), 3.52e3.49 (m, 1H), 3.43 (d,
J ¼ 17.0 Hz, 1H), 3.16 (d, J ¼ 14.5 Hz, 1H). 13C NMR (125 MHz, CDCl3)
Light yellow oil; 52% yield, 64 mg; 1H NMR (500 MHz, CDCl3)
d
7.19 (d, J ¼ 8.0 Hz, 2H), 6.90 (d, J ¼ 8.5 Hz, 2H), 3.91e3.83 (m, 1H),
3.17e3.10 (m, 2H), 3.05e3.00 (m, 1H), 2.98e2.91 (m, 1H), 2.28 (s,
3H), 1.92e1.84 (m, 2H), 1.74e1.58 (m, 4H). 13C NMR (125 MHz,
d
144.3, 134.1, 132.0, 131.2, 130.0, 129.1, 128.5, 128.2, 125.7, 126.5,
CDCl3)
d 147.8, 131.0, 130.1, 119.2, 113.0, 56.5, 47.7, 34.2, 27.4, 25.3,
126.1, 124.5, 122.9, 118.2, 118.1, 112.3, 111.6, 53.5, 53.3, 43.3, 34.6.
HRMS (ESI-TOF) m/z: [MþH]þ for C21H19N2S 331.1264, found
331.1268.
20.7, 20.3. HRMS (ESI-TOF) m/z: [MþH]þ for C14H19N2S 247.1264,
found 247.1275.
4.2.20. 1-(4-Chlorophenyl)-2-(thiocyanatomethyl)piperidine (3u)
4.3.5. 1-Benzyl-5-fluoro-2-(thiocyanatomethyl)indoline (5e)
White solid; 23% yield, 35 mg; mp 74e83 ꢀC. 1H NMR (500 MHz,
Yellow oil; 54% yield, 72 mg; 1H NMR (500 MHz, CDCl3)
d 7.22 (t,
J ¼ 9.0 Hz, 2H), 6.88 (d, J ¼ 8.5 Hz, 2H), 4.02e3.97 (m, 1H), 3.26 (dt,
J ¼ 12.5, 3.5 Hz, 1H), 3.17e3.12 (m, 1H), 3.03e2.97 (m, 1H), 2.94 (td,
J ¼ 10.0, 3.0 Hz, 1H), 1.96e1.84 (m, 2H), 1.75e1.51 (m, 4H). 13C NMR
CDCl3)
d
7.35e7.28 (m, 5H), 6.81 (d, J ¼ 7.0 Hz,1H), 6.72 (t, J ¼ 9.0 Hz,
1H), 6.25 (dd, J ¼ 4.0 Hz, 1H), 4.32 (d, J ¼ 16.0 Hz, 1H), 4.23 (d,
J ¼ 16.0 Hz,1H), 4.04e3.99 (m, 1H), 3.35e3.30 (m,1H) 3.18e3.17 (m,
2H), 2.98 (dd, J ¼ 16.5, 8.5 Hz, 1H). 13C NMR (125 MHz, CDCl3)
(125 MHz, CDCl3)
d 148.6, 129.4, 125.4, 119.0, 112.5, 56.1, 45.6, 33.2,
26.7, 24.9, 19.4. HRMS (ESI-TOF) m/z: [MþH]þ for C13H16ClN2S
d
158.1, 156.2, 148.1, 137.7, 129.0, 127.8, 127.6, 113.9 (d, J ¼ 12.5 Hz),
267.0717, found 267.0711.
112.6, 112.3 (d, J ¼ 25.0 Hz), 108.5 (d, J ¼ 5.0 Hz), 63.9, 53.3, 38.3,