750
Vol. 40
A. Klásek and V. Mrkvicˇka
General Procedures for the Reaction of 3 with Aliphatic Amines
and Anilines.
after column chromatography besides compound 8 in 27% yield
(128 mg) as colorless crystals (ethyl acetate), mp 161-163 °C; ir:
n 3152, 3131, 3061, 3019, 2965, 2834, 2707, 2630, 2574, 2079,
1623, 1612, 1519, 1462, 1434, 1362, 1268, 1239, 1158, 1143,
Method A.
-1 1
A solution of corresponding amine (2 mmoles) in benzene (20
ml) was added to a solution of 3 (616 mg, 2 mmoles) in benzene
(50 ml). The mixture was stirred at room temperature for 1 h and
subsequently refluxed for a time determined by tlc monitoring.
After cooling, deposited compound 4 was filtered with suction,
the reaction mixture was evaporated to half of its volume and a
further portion of deposited compound 4 was filtered with suction.
The filtrate was evaporated to dryness in vacuo and residue crys-
tallized from appropriate solvent or column chromatographed.
1125, 1028, 874, 800, 767, 692, 624 cm ; H nmr (DMSO-d6): d
2.83 (t, J = 7.8 Hz, 2H, Ar-CH2), 3.07 (t, J = 7.8 Hz, 2H, CH2N),
3.77 (s, 3H, OCH3), 3.80 (s, 3H, OCH3), 6.81 (dd, J = 7.9 and 2.1
Hz, 1H, H-6), 6.91 (d, J = 2.1 Hz, 1H, H-2), 6.94 (d, J = 7.9 Hz,
1H, H-5), 7.74 (br s, 3H, NH3+); 13C nmr (DMSO-d6): d 32.79
(Ar-C), 40.31 (C-N), 55.58 (OCH3), 55.67 (OCH3), 112.12
(C-5), 112.63 (C-2), 120.76 (C-6), 129.62 (C-1), 130.01 (SCN),
147.81 (C-4), 148.93 (C-3).
Anal. Calcd. for C11H16N2O2S (240.32): C, 54.98; H, 6.71; N,
11.66. Found: C, 54.77; H, 6.98; N, 11.49.
Method B.
N-Ethyl-4-thiocyanatoaniline (10).
The reactions were carried out by the same manner as is
described in Method A, but chloroform was used as solvent
instead of benzene.
Compound 10 was prepared by the reaction of 3 with N-ethyl-
aniline using Method A (reflux 4.5 h), and was obtained in 47%
yield (166 mg), mp 53-54 °C (hexane); for 10, mp 54 °C is
reported [21]; ir: n 3380, 2971, 2873, 2152, 1596, 1512, 1476,
1451, 1406, 1384, 1334, 1296, 1264, 1177, 1150, 1085, 815, 677
N-Benzyl-S-cyanothiohydroxylamine (6).
Compound 6 was prepared by the reaction of 3 with benzy-
lamine using Method A (reflux 3.5 h), and was obtained after col-
umn chromatography as pale yellow oil in 73% yield (239 mg);
ir: n 3301, 3029, 2854, 2136, 1600, 1494, 1457, 1410, 1339,
1309, 1294, 1204, 1080, 1033, 1024, 870, 789, 746, 698, 613,
598 cm-1, identical with that of compound 6 prepared according
to Ref. [16].
1
cm-1; H nmr (DMSO-d6): d 1.15 (t, J=7.1 Hz, 3H, CH3), 3.05
(m, 2H, NHCH2), 6.27 (t, J=4.8 Hz, 1H, NH), 6.63 (d, J=8.7 Hz,
2H, H-2 and H-6), 7.37 (d, J=8.7 Hz, 2H, H-3 and H-5); 13C nmr
(DMSO-d6): d 13.99, 36.88, 104.42, 112.96, 113.07, 134.79,
150.91; ms: m/z (%): 178 (M+, 42), 163 (100), 152 (12), 134 (13),
118 (6), 105 (18), 97 (11), 85 (6), 81 (22), 77 (7), 69 (42), 63 (8),
57 (20).
N,N-Dibenzyl-S-cyanothiohydroxylamine (7).
Anal. Calcd. for C9H10N2S (178.26): C, 60.64; H, 5.65; N,
15.72. Found: C, 60.81; H, 5.47; N, 15.49.
Compound 7 was prepared by the reaction of 3 with dibenzy-
lamine using Method A (reflux 3.5 h), and was obtained in 57%
yield (289 mg), mp 46-47 °C (hexane); ir: n 3025, 2849, 2127,
1600, 1495, 1453, 1446, 1370, 1360, 1311, 1253, 1204, 1101,
N-Benzyl-4-thiocyanatoaniline (11).
Compound 11 was prepared by the reaction of 3 with N-ben-
zylaniline using Method A (reflux 4.5 h) in 59% (283 mg), mp
41-2 °C (cyclohexane); for 11, mp 78 °C (ethanol) is reported
[22]. Compound 11 prepared by us according to Ref. [22]
exhibits mp 40-41 °C (cyclohexane); ir: n 3362, 3033, 2890,
2858, 2152, 1598, 1511, 1468, 1453, 1406, 1331, 1297, 1257,
1
1071, 1029, 979, 948, 911, 746, 698, 621, 607 cm-1; H nmr
(DMSO-d6): d 4.07 (s, 4H, two PhCH2), 7.37 (s, 10H, two Ph);
13C nmr (DMSO-d6): d 61.55, 110.35, 127.97, 128.47, 128.55,
128.97, 129.65, 136.17; ms: m/z (%): 196 (M+-SCN, 29), 120
(21), 106 (75), 91 (100), 77 (11), 65 (23), 59 (15).
Anal. Calcd. for C15H14N2S (254.35): C, 70.83; H, 5.55; N,
11.01. Found: C, 70.72; H, 5.75; N, 10.82.
-1
1179, 1121, 1092, 820, 742, 696, 673, 531 cm .
Anal. Calcd. for C14H12N2S (240.32): C, 69.97; H, 5.03; N,
11.66. Found: C, 69.71; H, 5.23; N, 11.42.
N-(2-(3,4-Dimethoxyphenyl)ethyl)-S-cyanothiohydroxylamine
(8).
2,5-Dimethyl-4-thiocyanatoaniline (12).
Compound 8 was prepared by the reaction of 3 with 2-(3,4-
dimethoxyphenyl)ethylamine using Method B (6 h at room tem-
perature), and was obtained after column chromatography as col-
orless oil in 54% yield (257 mg); ir: n 3273, 2964, 2940, 2837,
2133, 1607, 1592, 1516, 1462, 1437, 1419, 1351, 1326, 1264,
1233, 1157, 1141, 1069, 1026, 900, 860, 808, 763, 661 cm-1; 1H
nmr (CDCl3): d 2.85 (t, J = 6.7 Hz, 2H, ArCH2), 3.02 (t, J = 5.6
Hz, 1H, NH), 3.31 (dd, J = 6.7 and 5.6 Hz, 2H, CH2N), 3.85 (s,
3H, OCH3), 3.87 (s, 3H, OCH3), 6.70 (d, J = 2.1 Hz, 1H, H-2),
6.73 (dd, J = 7.9 and 2.1 Hz, 1H, H-6), 6.80 (d, J = 7.9 Hz, 1H, H-
5); 13C nmr (CDCl3): d 34.71 (Ar-C), 54.18 (C-N), 55.86
(OCH3), 55.89 (OCH3), 111.40 (C-5), 111.74 (C-2), 114.17
(SCN), 120.67 (C-6), 130.12 (C-1), 147.86 (C-4), 149.12 (C-3).
Anal. Calcd. for C11H14N2O2S (238.31): C, 55.44; H, 5.92; N,
11.76. Found: C, 55.12; H, 5.78; N, 11.85.
Compound 12 was prepared by the reaction of 3 with 2,5-
dimethylaniline using Method B (reflux 1.5 h), and was obtained
after column chromatography as the main reaction product in
65% yield (232 mg); colorless crystals, mp 59-61 °C (ethyl
acetate); for 12, mp 64 °C is reported [23]; ir: n 3467, 3428,
3349, 3213, 2920, 2863, 2151, 1630, 1558, 1498, 1461, 1401,
1376, 1306, 1298, 1264, 1036, 893, 856, 799, 716, 673, 639, 582
cm-1.
2-Amino-4,7-dimethyl-6-thiocyanatobenzothiazole (13).
Compound 13 was prepared by the reaction of 3 with 2,5-
dimethylaniline using Method B (reflux 1.5 h), and was obtained
after column chromatography besides compound12 in 18% yield
(85 mg); yellowish crystals, mp 240-241 °C; for 13, mp 231 °C is
reported [24]; ir: n 3400, 3309, 3082, 2951, 2923, 2764, 2153,
1657, 1581, 1530, 1465, 1455, 1374, 1296, 1118, 1062, 1118,
2-(3,4-Dimethoxyphenyl)ethylammonium Thiocyanate (9).
1
1062, 852, 744, 710, 598 cm-1; H nmr (DMSO-d6): d 2.40 (s,
Compound 9 was prepared by the reaction of 3 with 2-(3,4-
dimethoxyphenyl)ethylamine using Method B, and was obtained
3H, Ar-CH3), 2.51 (s, 3H, Ar-CH3), 7.39 (s, 1H, Ar-H), 7.86 (s,