تفاعل #69927

معادلة التفاعل

2-Bromothiophene-3-carboxylic acid methyl ester

4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester

Na2CO3

→

4-(3-methoxycarbonylthiophen-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester

المردود 92.8%

المذيبات

THF

ظروف التفاعل

المعالجة

1. 1
   أخرىThe mixture was degassed
2. 2
   أخرىpurged with nitrogen (3×)
3. 3
   أخرىthe mixture was again degassed
4. 4
   أخرىpurged with nitrogen (3×)
5. 5
   درجة الحرارةThe mixture was then cooled
6. 6
   أخرىthe layers were separated
7. 7
   workup.ADDITIONThe THF layer was diluted with EtOAc (150 mL)
8. 8
   غسيلwashed with saturated aqueous NaCl (50 mL)
9. 9
   تجفيفdried over Na2SO4
10. 10
    ترشيحThe material was filtered
11. 11
    أخرىpurified by chromatography with PE/EtOAc (20:1˜10:1)

الإجراء التجريبي

2-Bromothiophene-3-carboxylic acid methyl ester (3.0 g, 14.0 mmol, 1.0 eq.), 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester (4.2 g, 14.0 mmol, 1.0 eq.), THF (150 mL) and Na2CO3 (28 mL, 56 mmol, 4.0 eq.) were combined. The mixture was degassed and purged with nitrogen (3×). PdCl2(PPh3)2 (0.3 g, 0.4 mmol, 0.03 eq.) was added, and the mixture was again degassed and purged with nitrogen (3×), then heated at 80° C. overnight. The mixture was then cooled and the layers were separated. The THF layer was diluted with EtOAc (150 mL), washed with saturated aqueous NaCl (50 mL) and dried over Na2SO4. The material was filtered and applied onto a silica gel column and purified by chromatography with PE/EtOAc (20:1˜10:1) to yield 4-(3-methoxycarbonylthiophen-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester (4.2 g) as a yellow solid.

المصدر