Diisopropylamine → HCID 178494652, compound

Participants

Reaction Conditions

Reaction Steps

A solution of diisopropylamine (1.51 g) in tetrahydrofuran (15 ml), under nitrogen, cooled to −10° C. was treated with butyl lithium in hexane (6 ml, 2.5 M). The solution was cooled to −78° C. then treated dropwise with a solution of 4-picoline (1.40 g) in tetrahydrofuran (10 ml) followed by a solution of methyl 7-methoxy-2-methoxymethyl-3H-benzimidazole-4-carboxylate [1,25 g, Reference Example 3(a)] in tetrahydrofuran (15 ml). The brown solution was allowed to warm to room temperature and the resulting yellow suspension was filtered. The insoluble material was washed with a little tetrahydrofuran then air dried. The yellow solid (2.3 g) was dissolved in water (75 ml) and the solution extracted three times with dichloromethane (25 ml). The combined extracts were dried over magnesium sulphate and then evaporated. The resulting yellow solid (1.53 g) was subjected to flash chromatography on silica eluting initially with a mixture of methanol and dichloromethane (5:95, v/v) to give 1-(7-methoxy-2-methoxymethyl-3H-benzimidazol-4-yl)-2-(4-pyridyl)ethanone (0.39 g) recrystallised from toluene as a yellow solid, m.p. 218-220° C. with decomposition. [Elemental analysis:—C, 66.58; H, 5.53; N, 13.76%. Calculated:—C, 66.45; H, 5.50; N, 13.5%]; then eluting with a mixture of methanol and dichloromethane (1:9, v/v) to give 1,3-bis-(4-pyridyl)-2-(7-methoxy-2-methoxymethyl-3H-benzimidazol-4-yl)-propan-2-ol (0.4 g) recrystallised from methanol as a white solid, m.p. 210° C. with decomposition. [Elemental analysis:—C, 68.40; H, 5.94; N, 13.85%. Calculated:—C, 68.30; H, 5.98; N, 14.00%].

Provenance & Evidence