反应详情

Methyl 2-[2-(tert-butoxycarbonylamino)ethoxy]-4-methoxybenzoate (1.0 g, 3.07 mmol) was suspended in 20 ml of 3:1 tetrahydrofuran (THF):water, then chilled on ice for 30 min with stirring. Next there was added solid lithium hydroxide monohydrate (284 mg, 6.76 mmol) to the suspension, and the mixture was stirred at room temperature for 20 h at which time TLC (50:50:1 hexanes:EtOAc:AcOH) showed complete consumption of starting ester. The slurry was diluted with water (50 ml), washed twice with ethyl ether, then the aqueous layer was acidified to pH 2 with 1 N NaHSO4 to yield a heavy white slurry. The slurry was extracted twice with EtOAc, then the EtOAc layers were combined, washed with brine, dried over Na2SO4, and concentrated in vacuo to provide 2-[2-(tert-butoxycarbonylamino)ethoxy]-4-methoxybenzoic acid (870 mg, 91%) as a white crystalline solid.

1. customconsumption of starting ester
2. additionThe slurry was diluted with water (50 ml)
3. washwashed twice with ethyl ether
4. customto yield a heavy white slurry
5. extractionThe slurry was extracted twice with EtOAc
6. washwashed with brine
7. dry with materialdried over Na2SO4
8. concentrationconcentrated in vacuo