Ethyl orthoformate → HCID 58503275, compound

Participants

Reaction Steps

To a suspension of 20 (3.5 g, 8.29 mmol, 1 equiv) in MeCN (30 mL), triethyl orthoformate (6.2 mL, 41.46 mmol, 5 equiv) was added followed by 4 drops of sulfuric acid. The reaction mixture was heated at reflux for 1.5 h until starting material was disappeared (TLC). The precipitated product was filtered, washed with diethyl ether and dried under vacuum to afford the pure product 21 (RK-12) as a pale yellow solid (3 g, 85%). IR: 1745 (C═O str.), 1621, 1586, 1248, 1171, 759 (C—Cl str.) cm−1. 1H NMR (400 MHz, d6-DMSO): δ=3.71 (s, 3H, OCH3), 5.09 (s, 2H, CH2), 5.68 (s, 2H, CH2), 6.86 (d, J=8.7 Hz, 2H, Ar—H), 6.98-6.99 (m, 1H, Ar—H), 7.25-7.27 (m, 1H, Ar—H), 7.30 (d, J=8.7 Hz, 2H, Ar—H), 7.34-7.38 (m, 1H, Ar—H), 7.53-7.55 (m, 1H, Ar—H), 8.70 (s, 1H, Ar—C═N—H), 8.86 (s, 1H, Imid-H). MS (ESI+ve) m/z: 433.2 (M+H)+, 455.1 (M+Na)+.

Provenance & Evidence