تفاعل #59256

معادلة التفاعل

HCl

[(2-Ethoxycarbonyl-acetyl)-(3-methyl-butyl)-hydrazono]-thiophen-2-yl-acetic acid ethyl ester

sodium ethoxide

→

desired product ( 13a )

المردود 83.2%

5-Hydroxy-2-(3-methyl-butyl)-3-oxo-6-thiophen-2-yl-2,3-dihydro-pyridazine-4-carboxylic acid ethyl ester

المردود 83.2%

المذيبات

EtOH

ظروف التفاعل

المعالجة

1. 1
   استخلاصfollowed by liquid-liquid extraction with H2O/EtOAc
2. 2
   غسيلThe combined organic layer was washed with brine
3. 3
   تجفيفdried over MgSO4
4. 4
   تركيزconcentrated under reduced pressure
5. 5
   أخرىthe residue was purified by flash chromatography on silica gel

الإجراء التجريبي

To a solution of [(2-Ethoxycarbonyl-acetyl)-(3-methyl-butyl)-hydrazono]-thiophen-2-yl-acetic acid ethyl ester (12a) (380 mg, 1.0 mmol) in EtOH (6 mL) at room temperature, sodium ethoxide (Aldrich) (21 wt % in ethanol, 0.4 mL, 1.1 mmol) was added, and the resulting mixture was stirred for 30 min. Aqueous HCl (5%, 0.75 mL) was added slowly, and then followed by liquid-liquid extraction with H2O/EtOAc. The combined organic layer was washed with brine, dried over MgSO4, concentrated under reduced pressure and the residue was purified by flash chromatography on silica gel to give the desired product (13a) (280 mg, 83%) as yellow solid. LC-MS (ESI+): m/e=337.30 [M+1]+(exact ms: 336.11); 1H NMR (400 MHz, CDCl3): δ 7.89 (dd, 1H, J=3.6, 1.2 Hz), 7.39 (dd, 1H, J=5.2, 1.2 Hz), 7.10 (dd, 1H, J=5.2, 3.6 Hz), 4.53 (q, 2H, J=7.2 Hz), 4.22 (m, 2H), 1.73 (m, 2H), 1.68 (m, 1H), 1.50 (t, 3H, J=7.2 Hz), 0.99 (d, 6H, J=6.4 Hz).

المصدر