Molecules 2021, 26, 2740
14 of 24
2
-Isothiocyanatoethylbenzene (4a). Colorless oil. Yield 92% (0.3 g, 1.84 mmol) after flash
1
chromatography (hexane). H NMR (700 MHz, CDCl ):
δ = 7.36–7.34 (m, 2 H, CHAr), 7.30–
3
7
.27 (m, 1 H, CHAr), 7.23–7.22 (m, 2 H, CHAr), 3.73 (t, JHH = 7.0 Hz, 2 H, CH NCS), 3.00 (t,
2
JHH = 7.0 Hz, 2 H, CH2). 13C NMR (176 MHz, CDCl3):
28.9 (s, 2 C H), 128.8 (s, 2 C H), 127.3 (s, C H), 46.5 (s, CH NCS), 36.6 (s, CH ).
The analytical data are in agreement with those reported previously in the literature [63].
δ = 137.1 (s, C ), 131.0 (s, NCS),
Ar
1
×
×
Ar
Ar
Ar
2
2
(
Isothiocyanatomethyl)benzene (4b). Colorless oil. Yield 92% (0.273 g, 1.83 mmol) after flash
chromatography (hexane). 1H NMR (700 MHz, CDCl3):
= 7.42–7.39 (m, 2 H, CH ),
.37–7.34 (m, 1 H, CH ), 7.33–7.32 (m, 2 H, CH ), 4.71 (s, 2 H, CH NCS). C NMR
δ
Ar
1
3
7
Ar
Ar
2
(
1
176 MHz, CDCl3):
δ
= 134.3 (s, C ), 132.4 (s, NCS), 129.1 (s, 2
×
C H), 128.5 (s, C H),
Ar
Ar Ar
26.9 (s, 2
×
C H), 48.8 (s, CH NCS). The analytical data are in agreement with those
Ar 2
reported previously in the literature [63].
(
R)-1-isothiocyanatoethylbenzene (4c). Colorless oil. Yield 94% (0.306 g, 1.87 mmol) after flash
chromatography (hexane). The er was determined by HPLC using a Chiralpak ID column,
D
(
[
7
hexane); t
= 9.36 min, t
= 7.95 min (>99: 1 er). [
α
]
−
18.1 (c 1.0, CHCl ) (lit.
major
minor
25
3
D
1
α
]
−
18.3 (c 1.0, CHCl )). H NMR (700 MHz, CDCl ):
δ
= 7.41–7.38 (m, 2 H, CH ),
25
3
3
Ar
.34–7.32 (m, 3 H, CH ), 4.92 (q, J
= 6.8 Hz, 1 H, CHNCS), 1.68 (d, JHH = 6.8 Hz, 3 H,
= 140.3 (s, C ), 132.5 (s, NCS), 129.0 (s, 2
28.3 (s, C H), 125.5 (s, 2 C H), 57.2 (s, CHNCS), 25.1 (s, CH ). The concentration of
the sample for CD analysis was 0.51 mg/mL. The analytical data are in agreement with
those reported previously in the literature [63].
Ar
HH
13
CH3). C NMR (176 MHz, CDCl3):
1
δ
×
C H),
Ar
Ar
×
Ar
Ar
3
(S)-1-isothiocyanatoethylbenzene (4d). Colorless oil. Yield 92% (0.3 g, 1.84 mmol) after flash
chromatography (hexane). The er was determined by HPLC using a Chiralpak ID column
D
(
[
hexane); t
= 7.95 min, t
= 9.36 min (>99: 1 er). [
α
]
+17.5 (c 1.0, CHCl ) (lit.
major
minor
1
25 3
D
α
]
+17.6 (c 1.0, CHCl )). H NMR (700 MHz, CDCl ):
δ
= 7.41–7.38 (m, 2 H, CHAr),
25
3
3
7
.34–7.32 (m, 3 H, CH ), 4.92 (q, J
= 6.8 Hz, 1 H, CHNCS), 1.68 (d, JHH = 6.8 Hz, 3 H,
Ar
HH
δ
13
CH3). C NMR (176 MHz, CDCl3):
= 140.3 (s, C ), 132.5 (s, NCS), 129.0 (s, 2
×
C H),
Ar
Ar
128.3 (s, CArH), 125.5 (s, 2 CArH), 57.1 (s, CHNCS), 25.1 (s, CH ). The concentration of the
×
3
sample for CD analysis was 0.5 mg/mL. The analytical data are in agreement with those
reported previously in the literature [63].
1
-Isothiocyanatohexane (4e). Colorless oil. Yield 88% (0.251 g, 1.76 mmol) after flash chro-
1
matography (hexane). H NMR (700 MHz, CDCl ):
δ = 3.50 (t, JHH = 6.7 Hz, 2 H, CH NCS),
3
2
1
.71–1.67 (m, 2 H, CH ), 1.43–1.39 (m, 2 H, CH ), 1.35–1.27 (m, 4 H, 2
×
CH ), 0.90 (t,
2
2
2
13
JHH = 7.1 Hz, 3 H, CH3). C NMR (176 MHz, CDCl3):
δ = 129.7 (s, NCS), 45.2 (s, CH NCS),
2
3
1.1 (s, CH ), 30.1 (s, CH ), 26.3 (s, CH ), 22.6 (s, CH ), 14.0 (s, CH ). The analytical data are
2
2
2
2
3
in agreement with those reported previously in the literature [63].
2
-Isothiocyanatobutane (4f). Colorless oil. Yield 72% (0.166 g, 1.44 mmol) after flash chro-
1
matography (hexane). H NMR (700 MHz, CDCl ):
δ = 3.33 (d, JHH = 6.2 Hz, 2 H, CH NCS),
3
2
1.99 (sept, JHH = 6.5 Hz, 1 H, CH), 1.00 (t, JHH = 6.7 Hz, 6 H, 2
×
CH3). 13C NMR (176 MHz,
= 129.8 (s, NCS), 52.5 (s, CH NCS), 29.7 (s, CH), 19.8 (s, 2 CH ). The analytical
CDCl3):
δ
×
2
3
data are in agreement with those reported previously in the literature [63].
2
-Isothiocyanatooctane (4g). Colorless oil. Yield 97% (0.330 g, 1.94 mmol) after flash chro-
1
matography (hexane). H NMR (700 MHz, CDCl3):
δ = 3.77–3.72 (m, 1 H, CHNCS),
1
.65–1.60 (m, 1 H, H from CH ), 1.57–1.52 (m, 1 H, H from CH ), 1.47–1.42 (m, 1 H, H from
2
2
CH ), 1.39–1.33 (m, 1 H, H from CH ), 1.34 (d, J
= 6.5 Hz, 3 H, CH CH), 1.32–1.25 (m,
3
2
2
HH
1
3
6
H, 3
×
CH ), 0.88 (t, J
= 7.1 Hz, 3 H, CH3). C NMR (176 MHz, CDCl3): δ = 129.9 (s,
2
HH
NCS), 54.2 (s, CHNCS), 37.7 (s, CH ), 31.7 (s, CH ), 28.8 (s, CH CH), 26.1 (s, CH ), 22.6 (s,
2
2
3
2
CH ), 21.9 (s, CH ), 14.1 (s, CH ). The analytical data are in agreement with those reported
2
2
3
previously in the literature [63].
3
-Isothiocyanatopentane (4h). Colorless oil. Yield 82% (0.211 g, 1.64 mmol) after flash
1
chromatography (hexane). H NMR (700 MHz, CDCl ):
δ = 3.53–3.49 (m, 1 H, CHNCS),
3