تفاعل #91019

معادلة التفاعل

3,5-Dichloro-4-ethoxybenzoic acid

4-(Benzyloxy)-3-chloro-5-(cyclohexyloxy)benzoic acid

oxalyl chloride

tert-butyl 4-amino-2-methoxybenzoate

tert-Butyl 4-amino-2-methoxybenzoate

DMF

→

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

المردود 42.0%

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

المردود 42.0%

المذيبات

DCM

ظروف التفاعل

المعالجة

1. 1
   أخرىthe solvent was removed in vacuo
2. 2
   workup.DISSOLUTIONThe residue was dissolved in DCM (5 mL)
3. 3
   workup.STIRRINGstirred at RT for 16 h
4. 4
   غسيلThe mixture was sequentially washed with sat. aq. NaHCO3 (5 mL) and 1 M HCl (5 mL)
5. 5
   تركيزthe organic phase was concentrated in vacuo
6. 6
   أخرىThe residue was purified by silica gel chromatography (12 g, 0-100% EtOAc in isohexane)

الإجراء التجريبي

3,5-Dichloro-4-ethoxybenzoic acid (4) (75 mg, 0.32 mmol) in DCM (5 mL) was treated with oxalyl chloride (56 μL, 0.64 mmol) dropwise, followed by a drop of DMF. The reaction mixture was stirred at RT for 1 h, and then the solvent was removed in vacuo. The residue was dissolved in DCM (5 mL) and TEA (133 μL, 957 μmol) was added. The mixture was added to tert-butyl 4-amino-2-methoxybenzoate (3) (71 mg, 0.32 mmol) and stirred at RT for 16 h. The mixture was sequentially washed with sat. aq. NaHCO3 (5 mL) and 1 M HCl (5 mL), and the organic phase was concentrated in vacuo. The residue was purified by silica gel chromatography (12 g, 0-100% EtOAc in isohexane) to afford tert-butyl 4-(3,5-dichloro-4-ethoxybenzamido)-2-methoxybenzoate (5) (59 mg, 42%) as a white solid: m/z 384 [M−tBu+2H]+ (ES+); 1H-NMR (400 MHz, DMSO-d6) δ: 10.51 (1H, s), 8.09 (2H, s), 7.63 (1H, d), 7.60 (1H, d), 7.43 (1H, dd), 4.15 (2H, q), 3.81 (3H, s), 1.51 (9H, s), 1.41 (3H, t).

المصدر