Formamide → 6,7,8,9-tetrahydro-1H-[1]benzofuro[3,2-d]pyrimidin-4-one

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Reaction Conditions

Reaction Steps

A 15 mL flask was charged with 3-amino-4,5,6,7-tetrahydro-benzo[b]thiophene-2-carboxylic acid ethyl ester (synthesized by the route described in Example 5, Step A; 0.50 g, 2.4 mmol), formamide (4.8 mL), and KOtBu (95%; 0.56 g, 4.8 mmol) under N2. After heating at 110° C. for 12 h, the mixture was poured over cold satd. aq. NH4Cl (10 mL). Filtration afforded the desired product (0.31 g). MS: No signal. 1H NMR (400 MHz, d6-DMSO) δ ppm 8.00 (s, 1H), 2.74-2.69 (m, 2H), 2.56-2.51 (m, 2H), 1.92-1.81 (m, 2H), 1.79-1.69 (m, 2H).

Provenance & Evidence