Diisopropylamine → HCID 178491390, compound

Participants

Reaction Conditions

Reaction Steps

A solution of diisopropylamine (0.47 ml) in tetrahydrofuran (6 ml), cooled to −10° C., was treated dropwise, with a solution of butyl lithium in hexanes (1.2 ml, 2.5 M). The resulting solution was stirred for 10 minutes, then cooled to −78° C. and then treated dropwise with a solution of 4-picoline (0.29 ml) in tetrahydrofuran (1 ml). This solution was stirred for 30 minutes then treated with a solution of methyl 2-cyclopentyl-7-methoxy-3H-benzimidazole-4-carboxylate [0.274 g, Reference Example 3(t)] in tetrahydrofuran (2 ml). The cold bath was removed and the reaction mixture stirred for 15 minutes at ambient temperature. The mixture was quenched with water, then diluted with ethyl acetate. The organic phase was separated then washed with brine, then dried over magnesium sulphate and then evaporated. The residue was subjected to flash chromatography on silica, eluting with a mixture of methanol and dichloromethane (8:92, v/v), to give the title compound (0.126 g) as a white solid. [Elemental analysis:—C, 71.7; H, 6.40; N, 12.5%. Calculated:—C, 71.6; H, 6.31; N, 12.5%]. NMR (CDCl3): δ 1.63-2.05(m, 6H), 2.2(m, 2H), 3.33(m, 1H), 4.11(s, 3H), 4.35(s, 2H), 6.72(d, J=8 Hz, 1H), 7.23(m, 2H), 7.82(d, J=8 Hz, 1H), 8.6(m, 2H).

Provenance & Evidence