Reacción #2289417

Ecuación de reacción

2-(6-methoxypyridin-2-yl)ethanamine

hydrogen chloride CPME

ethyl glyoxylate toluene

hydrogen chloride CPME

ethyl glyoxylate toluene

→

ethyl 2-hydroxy-5,6,7,8-tetrahydro-1,6-naphthyridine-5-carboxylate hydrochloride

Rendimiento 82.0%

Disolventes

EtOH

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturaunder reflux for 8 hr
2. 2
   Temperaturathe mixture was heated again
3. 3
   Temperaturaunder reflux for 16 hr
4. 4
   ConcentraciónThe reaction mixture was concentrated under reduced pressure to half volume
5. 5
   workup.ADDITIONto the residue was added diethyl ether (ca. 150 mL)
6. 6
   FiltraciónThe precipitate was collected by filtration
7. 7
   Lavadowashed with EtOH/diethyl ether

Procedimiento

A solution of 2-(6-methoxypyridin-2-yl)ethanamine (14.43 g, 94.81 mmol), 4N hydrogen chloride/CPME (26.1 mL, 104.29 mmol) and 47% ethyl glyoxylate/toluene solution (polymer form) (30.0 mL, 142.22 mmol) in EtOH (175 mL) was heated under reflux for 8 hr. To the reaction mixture were added 4N hydrogen chloride/CPME (26.1 mL, 104.29 mmol) and 47% ethyl glyoxylate/toluene solution (polymer form) (30.0 mL, 142.22 mmol), and the mixture was heated again under reflux for 16 hr. The reaction mixture was concentrated under reduced pressure to half volume, and to the residue was added diethyl ether (ca. 150 mL). The precipitate was collected by filtration, and washed with EtOH/diethyl ether to give crude ethyl 2-hydroxy-5,6,7,8-tetrahydro-1,6-naphthyridine-5-carboxylate hydrochloride (20.01 g, 77 mmol, 82%) as an off-white powder.

Fuente