反应详情

A solution of rac-7-{[2-(tert-butyl-dimethyl-silanyl)-1-dimethylsulfamoyl-1H-imidazol-4-yl]-hydroxy-methyl}-5-methyl-benzofuran-2-carboxylic acid ethyl ester (470 mg; example 52.b) in EtOH (16 ml) was treated with 10% Pd/C (117 mg) and hydrogenated for 48 hrs at 100 bar and 100° C. The reaction mixture was cooled to r.t., filtrated and concentrated. The residue was dissolved in EtOH (5 ml) and treated with 3N HCl (5 ml). The solution was heated to 100° C. for 3 hrs, then concentrated. The residue was taken up in water. The solution was made basic by the addition of K2CO3 and extracted with CH2Cl2/MeOH 4:1. The organics were dried over MgSO4, filtrated and concentrated. The crude product was purified by column chromatography (silica gel; gradient: CH2Cl2→CH2Cl2/MeOH 9:1) to give 7-(1H-imidazol-4-ylmethyl)-5-methyl-benzofuran-2-carboxylic acid ethyl ester (10 mg) as amorphous off-white solid. MS (ISP): 285.1 ((M+H)+.).

1. filtrationfiltrated
2. concentrationconcentrated
3. dissolutionThe residue was dissolved in EtOH (5 ml)
4. additiontreated with 3N HCl (5 ml)
5. temperatureThe solution was heated to 100° C. for 3 hrs
6. concentrationconcentrated
7. additionThe solution was made basic by the addition of K2CO3
8. extractionextracted with CH2Cl2/MeOH 4:1
9. dry with materialThe organics were dried over MgSO4
10. filtrationfiltrated
11. concentrationconcentrated
12. customThe crude product was purified by column chromatography (silica gel; gradient: CH2Cl2→CH2Cl2/MeOH 9:1)