PAPER
Acid-Catalyzed Transformations of tert-N-Furfurylcarboxamides
3093
IR (nujol): 3411, 3315, 3103, 1626, 1598, 1510, 1456, 1375, 1346,
1251, 1201, 1139, 1110, 1016, 979, 960, 844, 779 cm–1.
1 H, HFur), 6.05 (d, J = 3.0 Hz, 1 H, HFur), 6.92 (s, 1 H, HPy), 7.08 (br
s, 2 H, NH2), 7.15–7.22 (m, 2 H, HPh), 7.38–7.40 (m, 3 H, HPh).
1H NMR (300 MHz, DMSO-d6): d = 1.35 (s, 9 H, t-Bu), 2.20 (s,
3 H, CH3), 2.48 (s, 3 H, CH3), 2.73 (s, 3 H, CH3), 4.71 (s, 2 H, CH2),
5.63 (br s, 2 H, NH2), 5.97 (d, J = 3.0 Hz, 1 H, HFur), 6.09 (d, J = 3.0
Hz, 1 H, HFur), 7.00 (s, 1 H, HPy).
MS: m/z (%) = 371 (21) [M+], 297 (10), 278 (25), 277 (70), 272
(19), 271 (14), 229 (13), 221 (36), 206 (19), 205 (68), 204 (50), 203
(13), 179 (33), 178 (47), 177 (28), 176 (15), 166 (14), 150 (16), 137
(15), 136 (56), 133 (17), 132 (16), 110 (58), 101 (35), 96 (51), 95
(100), 94 (18), 91 (20), 67 (14), 65 (23), 59 (42), 57 (73), 56 (20),
55 (21), 53 (31), 51 (25), 45 (19), 43 (27), 42 (20).
MS: m/z (%) = 391 (26) [M+], 297 (21), 272 (10), 207 (11), 206
(15), 205 (79), 186 (27), 178 (17), 96 (12), 95 (100), 91 (18), 59
(43), 57 (27), 55 (11), 43 (51), 42 (20).
Anal. Calcd for C22H21N3O2S: C, 67.50; H, 5.41; N, 10.73. Found:
C, 67.59; H, 5.46; N, 10.65.
N2-(5-Methyl-2-furylmethyl)-N2-phenyl-3-amino-5-bromo-4-
methoxymethyl-6-methylthieno[2,3-b]pyridine-2-carboxamide
(6f)
Mp 155–157 °C.
Anal. Calcd for C20H25N3O2S: C, 64.66; H, 6.78; N, 11.31. Found:
C, 64.74; H, 6.71; N, 11.35.
IR (nujol): 3396, 3306, 3062, 1577, 1527, 1495, 1460, 1365, 1334,
1296, 1265, 1207, 1191, 1147, 1091, 1022, 993, 956, 908, 788, 756
cm–1.
N2-(tert-Butyl)-N2-(5-methyl-2-furylmethyl)-3-amino-5-bro-
mo-4-methoxymethyl-6-methylthieno[2,3-b]pyridine-2-carbox-
amide (6c)
Mp 99–101 °C.
1H NMR (300 MHz, DMSO-d6): d = 2.20 (s, 3 H, CH3), 2.61 (s, 3 H,
CH3), 3.39 (s, 3 H, CH3OCH2), 4.91 (s, 2 H, CH2), 5.02 (s, 2 H,
CH2), 5.94 (d, J = 3.0 Hz, 1 H, HFur), 6.06 (d, J = 3.0 Hz, 1 H, HFur),
7.18–7.27 (m, 4 H, HPh + NH2), 7.39–7.45 (m, 3 H, HPh).
IR (nujol): 3408, 3313, 1622, 1556, 1533, 1462, 1389, 1334, 1255,
1190, 1085, 1016, 968, 903, 793 cm–1.
1H NMR (300 MHz, DMSO-d6): d = 1.36 (s, 9 H, t-Bu), 2.19 (s,
3 H, CH3), 2.71 (s, 3 H, CH3), 3.41 (s, 3 H, CH3OCH2), 4.69 (s, 2 H,
CH3OCH2), 5.06 (s, 2 H, CH2-Fur), 5.74 (br s, 2 H, NH2), 5.95 (d,
J = 3.0 Hz, 1 H, HFur), 6.10 (d, J = 3.0 Hz, 1 H, HFur).
MS: m/z (%) = 501 (24), 500 (10), 499 (24), 407 (23), 405 (22), 315
(49), 314 (12), 313 (48), 288 (10), 286 (10), 253 (10), 187 (14), 186
(75), 174 (16), 96 (20), 95 (100), 93 (20), 91 (17), 76 (10), 65 (13),
59 (10), 51 (16), 45 (12), 44 (37), 43 (39), 42 (17), 41 (18).
Anal. Calcd for C23H22BrN3O3S: C, 55.21; H, 4.43; N, 8.40. Found:
C, 55.34; H, 4.32; N, 8.51.
MS: m/z (%) = 480 (3) [M+], 479 (21), 388 (12), 387 (46), 386 (16),
385 (47), 382 (26), 380 (23), 365 (12), 363 (16), 348 (16), 331 (15),
316 (14), 315 (56), 314 (19), 313 (58), 307 (19), 300 (20), 299 (36),
297 (27), 289 (18), 288 (25), 287 (21), 286 (13), 283 (26), 281 (16),
255 (35), 253 (19), 219 (17), 207 (13), 191 (32), 174 (33), 173 (16),
166 (54), 163 (13), 136 (74), 130 (12), 124 (14), 111 (18), 110 (57),
101 (14), 96 (29), 95 (100), 91 (23), 82 (14), 65 (13), 59 (30), 57
(30), 53 (18), 52 (15), 45 (18), 43 (37), 42 (18).
N2,N2-Di(5-methyl-2-furylmethyl)-3-amino-4-methoxymethyl-
6-methylthieno[2,3-b]pyridine-2-carboxamide (6g)
Mp 68–70 °C.
IR (nujol): 3400, 3301, 1598, 1498, 1450, 1429, 1361, 1334, 1282,
1249, 1224, 1132, 1091, 1022, 993, 975, 933, 852, 802, 754 cm–1.
1H NMR (300 MHz, DMSO-d6): d = 2.21 (s, 6 H, CH3), 2.54 (s, 3 H,
CH3), 3.38 (s, 3 H, CH3OCH2), 4.59 (s, 4 H, CH2), 4.82 (s, 2 H,
CH2), 6.00 (d, J = 3.0 Hz, 2 H, HFur), 6.19 (d, J = 3.0 Hz, 2 H, HFur),
6.34 (br s, 2 H, NH2), 7.23 (s, 1 H, HPy).
Anal. Calcd for C21H26BrN3O3S: C, 52.50; H, 5.45; N, 8.75. Found:
C, 52.42; H, 5.41; N, 8.88.
MS: m/z (%) = 439 (9) [M+], 344 (24) [M+ – CH2(Fur)CH3], 236
(22), 235 (70), 203 (17), 175 (13), 136 (25), 128 (15), 111 (26), 110
(36), 96 (18), 95 (100), 81 (51), 67 (13), 66 (11), 59 (34), 57 (10),
53 (15), 46 (17), 45 (28), 43 (28), 42 (20), 41 (17).
N2-(5-Methyl-2-furylmethyl)-N2-phenyl-3-amino-4-meth-
oxymethyl-6-methylthieno[2,3-b]pyridine-2-carboxamide (6d)
Mp 163–165 °C.
IR (nujol): 3358, 3269, 2327, 1932, 1597, 1566, 1537, 1462, 1377,
1313, 1275, 1196, 1111, 1020, 972, 904, 864, 760, 729 cm–1.
Anal. Calcd for C23H25N3O4S: C, 62.85; H, 5.73; N, 9.56. Found: C,
62.96; H, 5.78; N, 9.44.
1H NMR (300 MHz, DMSO-d6): d = 2.21 (s, 3 H, CH3), 2.45 (s, 3 H,
CH3), 3.69 (s, 3 H, CH3OCH2), 4.79 (s, 2 H, CH2), 4.90 (s, 2 H,
CH2), 5.94 (d, J = 3.0 Hz, 1 H, HFur), 6.06 (d, J = 3.0 Hz, 1 H, HFur),
7.15 (s, 1 H, HPy), 7.19–7.24 (m, 2 H, HPh), 7.25 (br s, 2 H, NH2),
7.38–7.42 (m, 3 H, HPh).
MS: m/z (%) = 421 (25) [M+], 327 (21), 302 (15), 270 (12), 236
(17), 235 (76), 219 (11), 208 (14), 203 (32), 187 (15), 186 (67), 175
(32), 131 (12), 119 (14), 96 (14), 65 (100), 67 (14), 59 (18), 44 (15),
43 (22).
N2,N2-Di(5-methyl-2-furylmethyl)-3-amino-4,6-dimethyl-
thieno[2,3-b]pyridine-2-carboxamide (6h)
Mp 145–146 °C.
IR (nujol): 3487, 3357, 1672, 1587, 1546, 1359, 1288, 1236, 1189,
1153, 1068, 1022, 987, 950, 918, 858, 842, 784, 759, 742 cm–1.
1H NMR (200 MHz, DMSO-d6): d = 2.23 (s, 6 H, CH3), 2.49 (s, 3 H,
CH3), 2.73 (s, 3 H, CH3), 4.62 (s, 4 H, CH2), 6.01 (d, J = 3.0 Hz,
2 H, HFur), 6.10–6.24 (m, 4 H, HFur + NH2), 7.03 (s, 1 H, HPy).
MS: m/z (%) = 409 (29) [M+], 316 (16), 315 (45), 314 (88), 298
(13), 297 (59), 273 (10), 271 (10), 207 (13), 206 (36), 205 (100),
204 (10), 179 (14), 178 (15), 177 (15), 150 (11), 149 (10), 136 (51),
111 (10), 110 (60), 96 (15), 95 (76), 59 (22), 57 (12), 51 (11), 49
(10), 42 (22), 41 (14), 39 (1).
Anal. Calcd for C23H23N3O3S: C, 65.54; H, 5.50; N, 9.97. Found: C,
65.62; H, 5.55; N, 10.04.
N2-(5-Methyl-2-furylmethyl)-N2-phenyl-3-amino-4,6-dimeth-
ylthieno[2,3-b]pyridine-2-carboxamide (6e)
Mp 176–177 °C.
Anal. Calcd for C22H23N3O3S: C, 64.53; H, 5.66; N, 10.26. Found:
C, 64.63; H, 5.72; N, 10.19.
IR (nujol): 3516, 3325, 3066, 1591, 1547, 1493, 1458, 1406, 1369,
1305, 1248, 1188, 1145, 1107, 1072, 1024, 951, 892, 852, 784, 756
cm–1.
1H NMR (300 MHz, DMSO-d6): d = 2.20 (s, 3 H, CH3), 2.39 (s, 3 H,
CH3), 2.69 (s, 3 H, CH3), 4.89 (s, 2 H, CH2), 5.93 (d, J = 3.0 Hz,
N2,N2-Di(5-methyl-2-furylmethyl)-3-amino-5-bromo-4-meth-
oxymethyl-6-methylthieno[2,3-b]pyridine-2-carboxamide (6i)
Mp 107–109 °C.
Synthesis 2008, No. 19, 3088–3098 © Thieme Stuttgart · New York