Reacción #440620

Ecuación de reacción

diethylamine

compound 5

4-[bromo-(4-caboxy-phenyl)-methylene]-piperidine-1-carboxylic acid tert-butyl ester

isobutylchloroformate

→

compound 6

Rendimiento 73.0%

4-[bromo-(4-diethylcarbamoyl-phenyl)-methylene]-piperidine-1-carboxylic acid tert-butyl ester

Rendimiento 73.0%

Disolventes

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroAfter 1.5 hrs the solvents were evaporated
2. 2
   Otrothe residue was partitioned between ethyl acetate and water
3. 3
   LavadoThe organic phase was washed with brine
4. 4
   Secadodried over MgSO4
5. 5
   OtroRemoval of solvents
6. 6
   Otroprovided a crude product, which
7. 7
   Otrowas purified by flash chromatography

Procedimiento

To a solution of compound 5 (1.0 g, 2.5 mmol) in dry dichloromethane (10 mL) at −20° C. was added isobutylchloroformate (450 mg, 3.3 mmol). After 20 min at −20° C. diethylamine (4 mL) was added and the reaction was allowed to warm to room temperature. After 1.5 hrs the solvents were evaporated and the residue was partitioned between ethyl acetate and water. The organic phase was washed with brine and dried over MgSO4. Removal of solvents provided a crude product, which was purified by flash chromatography to give compound 6 as white needles (800 mg, 73%): IR (NaCl) 3051, 2975, 1694, 1633, 1416, 1281, 1168, 1115 cm−1; 1H NMR (CDCl3) δ1.13 (br, 3H), 1.22 (br, 3H), 1.44 (s, 9H),2.22 (t, J=5.5 Hz, 2H), 2.62 (t, J=5.5 Hz, 2H), 3.33 (m, 4H), 3.55 (m, 2H), 7.31 (d, J=8.0 Hz, 2H), 7.36 (d, J=8.0 Hz, 2H); 13C NMR (CDCl3) δ12.71, 14.13, 28.3, 31.5, 34.2, 39.1, 43.2, 79.7, 115.9, 126.3, 129.3, 136.8, 137.1, 140.6, 154.6, 170.

Fuente