反应详情

4-[((9-Ethylcarbazol-3-yl)amino]-5-methylthiothiophene-2-carboxamidine: The same procedure as in Example 253, step (b) was followed using 80 mg (0.21 mmol) of methyl 4-[(9-ethylcarbazol-3-yl)amino]-5-methylthiothiophene-2-carboxylate (as prepared in previous step), 2 mL of trimethylaluminum (2.0 M in toluene, 4 mmol), 216 mg of ammonium chloride (4 mmol) and 2 mL of toluene, and purified on a 2-g silica SPE column with 5% MeOH—CH2Cl2 to afford 56 mg (70%) of the title compound as a yellow foam. 1H-NMR (DMSO-d6, 400 MHz) δ 1.31 (t, 3H, J=7.0 Hz),2.50 (s, 3H), 4.42 (q, 2H, J=7.0Hz), 7.14 (m, 1H), 7.27 (dd, 1H, J=8.7,2.1 Hz), 7.43 (m, 1H), 7.56 (m, 2H), 7.82 (d, 1H, J=2.0 Hz), 7.87 (s, 1H), 7.92 (s, 1H), 8.10 (d, 1H, J=7.7 Hz), 9.11 (br s, 4H). Mass spectrum (ESI, m/z): Calcd. for C20H20N4S2, 381.1 (M+H), found 381.3.

1. custompurified on a 2-g silica SPE column with 5% MeOH—CH2Cl2