反应详情

To a solution of N-formyl-Tyr(3-tBu)-OMe (23.8 g, 85.3 mmol) in THF (400 ml), 1.0M borane-THF complex (170 ml) was added dropwise under cooling with ice over 30 min. The mixture was stirred for 20 min., mixed with methanol (50 ml) and further stirred for 30 min. The reaction mixture was mixed with 33% hydrobromic acid/acetic acid (31 ml) and stirred for 2 hours. The mixture was neutralized by saturated aqueous NaHCO3 under cooling with ice and extracted with chloroform. The organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate and evaporated to remove the solvent under reduced pressure. The thus obtained residue was subjected to silica gel column chromatography (developing solvent: chloroform:methanol=20:1), giving N-Me-Tyr(3-tBu)-OMe (20.3 g, 90%).

1. temperatureunder cooling with ice over 30 min
2. stirringfurther stirred for 30 min
3. stirringstirred for 2 hours
4. temperatureunder cooling with ice
5. extractionextracted with chloroform
6. washThe organic layer was washed with saturated brine
7. dry with materialdried over anhydrous magnesium sulfate
8. customevaporated
9. customto remove the solvent under reduced pressure