Water → HCID 178491329, compound

Participants

Reaction Steps

A stirred solution of methyl 2-cyclopropyl-7-methoxy-3H-benzimidazole-4-carboxylate [15.5 g, Reference Example 3(v)], in dry tetrahydrofuran (220 ml), at −78° C. and under nitrogen, was treated dropwise over 3 hours with a solution of diisobutylaluminium hydride in dichloromethane (270 ml, 1.0M). The reaction mixture was allowed to warm to room temperature over 30 minutes, then cooled to −78° C., then treated dropwise with water (27 ml), then allowed to warm to room temperature. The reaction mixture was diluted with ice-water (500 ml) and the pH of the mixture was adjusted to above 12 by the addition of aqueous sodium hydroxide (750 ml, 1M). The resulting white suspension was filtered to yield a clear filtrate which was extracted seven times with ethyl acetate (500 ml). The combined extracts were dried over magnesium sulphate and then evaporated to yield the title compound as a cream coloured powder (10.13 g).

Provenance & Evidence