Some common heterocyclic compound, 3314-30-5, name is 1H-Benzo[d]imidazole-2-carbaldehyde, molecular formula is C8H6N2O, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Formula: C8H6N2O
General procedure: A suspension of methyl 2-(2-aminoethyl)-1 ,3-thiazole-4-carboxylate (5) (1.96 g, 10.52 mmol), 1 H- benzimidazole-2-carbaldehyde (2.31 g, 15.79 mmol) and DIPEA (1.83 ml, 10.52 mmol) in MeOH (100 ml) was stirred at room temperature for 12 h. The reaction mixture was cooled to 0°C, NaBH4 (0.597 g, 15.79 mmol) was added and the mixture stirred at room temperature for 2 h. The reaction mixture was concentrated in vacuo and the residue dissolved in EtOAc (100 ml) and washed with saturated NC03 (2 x 50 ml). The combined aqueous layers were extracted with EtOAc (3 x 50 ml) and the combined organic layers dried (MgS04), filtered and evaporated in vacuo. Purification by flash column chromatography (KP- NH, eluting with a gradient of 0-10percent MeOH / DCM) afforded the title compound (1.4 g, 38percent, 90percent purity) as a tan solid. 1 H-NMR (Methanol-d4, 250 MHz): d[ppm]= 8.27 (s, 1 H), 7.60 – 7.49 (m, 2H), 7.29 – 7.17 (m, 2H), 4.09 (s, 2H), 3.92 (s, 3H), 3.26 (t, J = 6.3 Hz, 2H), 3.10 (t, J = 6.8 Hz, 2H) HPLCMS (Method A): [m/z]: 317 [M+H]+In a similar fashion using general procedure 3, 1-(2-aminoethyl)-N-[(3-chloropyridin-2-yl)methyl]-1 H- pyrazole-4-carboxamide dihydrochloride (261 ) (200 mg, 0.54 mmol), 1 H-benzimidazole-2-carbaldehyde (94.5 mg, 0.65 mmol) and DIPEA (0.38 ml, 2.16 mmol) in MeOH (8 ml) at room temperature for 16 h, followed by addition of NaBH^ (30.6 mg, 0.81 mmol) gave the title compound (127 mg, 56percent) as a pale green foam after purification by basic prep-HPLC. 1 H-NMR (DMSO-d6, 500 MHz): d[ppm]= 12.17 (s, 1 H), 8.51 – 8.46 (m, 2H), 8.23 (s, 1 H), 7.92 (dd, J = 8.1 , 1.4 Hz, 1 H), 7.90 (s, 1 H), 7.58 – 7.41 (br m, 2H), 7.37 (dd, J = 8.1 , 4.7 Hz, 1 H), 7.17- 7.08 (m, 2H), 4.62 (d, J = 5.6 Hz, 2H), 4.23 (t, J = 6.2 Hz, 2H), 3.92 (br s, 2H), 2.98 (br s, 2H) HPLCMS (Method C): [m/z]: 410.2 [M+H]+
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3314-30-5, its application will become more common.
Reference:
Patent; VIFOR (INTERNATIONAL) AG; DUeRRENBERGER, Franz; BUHR, Wilm; BURCKHARDT, Susanna; BURGERT, Michael; KALOGERAKIS, Aris; REIM, Stefan; MANOLOVA, Vania; BOYCE, Susan; YARNOLD, Christopher John; PENA, Paula; SHEPHERD, Jon; LECCI, Cristina; JARJES-PIKE, Richard; SCOTT, John; (416 pag.)WO2017/68089; (2017); A2;,
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