Reaktion #91020

Reaktionsgleichung

tert-butyl 4-(3,5-dichloro-4-ethoxybenzamido)-2-methoxybenzoate

tert-Butyl 4-(3,5-dichloro-4-ethoxybenzamido)-2-methoxybenzoate

boron trichloride

water

NaHCO3

→

4-(3,5-dichloro-4-ethoxybenzamido)-2-hydroxybenzoic acid

Ausbeute 24.0%

Lösungsmittel

DCM

DCM

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITat RT for 2 h
2. 2
   TemperaturThe reaction mixture was cooled to 0° C.
3. 3
   FiltrationThe resulting white precipitate was collected by filtration
4. 4
   Waschenwashed with water (2 mL)
5. 5
   SonstigeThe solid was dried
6. 6
   Sonstigepurified by capture and release on SAX
7. 7
   Wascheneluting with 5% AcOH in THF

Vorschrift

A solution of tert-butyl 4-(3,5-dichloro-4-ethoxybenzamido)-2-methoxybenzoate (5) (55 mg, 0.13 mmol) in DCM (5 mL) was cooled to 0° C. and treated dropwise with a solution of 1 M boron trichloride in DCM (349 μL, 349 μmol). The reaction mixture was stirred at 0° C. for 1 h and then at RT for 2 h. The reaction mixture was cooled to 0° C. and water (0.5 mL) and sat. aq. NaHCO3 (2 mL) were added. The resulting white precipitate was collected by filtration and washed with water (2 mL). The solid was dried, then purified by capture and release on SAX, eluting with 5% AcOH in THF to afford 4-(3,5-dichloro-4-ethoxybenzamido)-2-hydroxybenzoic acid (AAA-057) (11 mg, 24%) as a white solid: m/z 370 [M+H]+ (ES+), 368 [M−H]− (ES−); 1H-NMR (400 MHz, DMSO-d6) δ: 10.51 (1H, s), 8.06 (2H, s), 7.76 (1H, d), 7.48 (1H, d), 7.28 (1H, dd), 4.14 (2H, q), 1.91 (1H, s), 1.40 (3H, t), 1.35 (1H, s).

Quelle