Cesium carbonate → HCID 19367647, compound

Participants

Reaction Steps

Ethyl 4-methyl-1H-[1]-benzothieno[2,3-f]indole-2-carboxylate (1.0 g, 3.2 mmol) was suspended in a mixture of methanol (110 ml) and water (30 ml). Caesium carbonate (10 g) was added and the mixture was heated at reflux under nitrogen for 2 h. The solution was allowed to cool to room temperature, and the methanol was removed in vacuo. The solution was acidified with 0.1 Molar Hydrochloric acid and the resulting yellow precipitate was collected by filtration and washed with water. The wet precipitate was dissolved in acetone and the solvent removed in vacuo to give the product as a yellow solid with m.p. 271-272° C.; δH [2H6 ]-DMSO 11.88 (1H, s, 1-NH), 8.29 (1H, dd, J 6, 3, 9-H), 8.18 (1H, s, 10-H), 7.89-7.99 (1H, m, 6-H), 7.44-7.54 (2H, m, 7-H, 8-H), 7.35 (1H, d, J 2, 3-H), 2.72 (3H, s, 4-CH3), m/z (%) 281 (90, M+), 263 (100) 235 (69).

Provenance & Evidence