反应详情

A solution of 4.8 g of lithium hydroxide monohydrate in 100 ml of water was added to a solution of 11.6 g of ethyl 1-[(2'-t-butoxycarbonylbiphenyl-4-yl)methyl]-4-(1-hydroxy-1-methylethyl)-2-propylimidazole-5-carboxylate [prepared as described in step (a) above] in 60 ml of dioxane, and the resulting mixture was stirred at room temperature for 16 hours. The dioxane was removed by distillation under reduced pressure, and then the concentrate was mixed with ice-water and with ethyl acetate, after which 114 ml of 1N aqueous hydrochloric acid were added. The ethyl acetate layer was separated, dried over anhydrous magnesium sulfate and freed from the solvent by distillation under reduced pressure. The crystalline residue was triturated in diisopropyl ether and collected by filtration to give 9.09 g of the title compound, melting at 155°-157° C.

1. customThe dioxane was removed by distillation under reduced pressure
2. additionthe concentrate was mixed with ice-water and with ethyl acetate
3. additionafter which 114 ml of 1N aqueous hydrochloric acid were added
4. customThe ethyl acetate layer was separated
5. dry with materialdried over anhydrous magnesium sulfate
6. distillationfreed from the solvent by distillation under reduced pressure
7. customThe crystalline residue was triturated in diisopropyl ether
8. filtrationcollected by filtration