Reaktion #44012

Reaktionsgleichung

HCl

4-methoxylpyridine

CbzCl

ethylmagnesium bromide

→

82

Ausbeute 89.9%

benzyl 2-ethyl-4-oxo-3,4-dihydropyridine-1(2H)-carboxylate

Ausbeute 89.9%

Lösungsmittel

toluene

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITAfter 1 hr
2. 2
   SonstigeThe mixture was separated
3. 3
   Waschenthe organic layer was washed with sat. NaHCO3 and brine
4. 4
   SonstigeIt was dried
5. 5
   Einengenconcentrated

Vorschrift

To a solution of 4-methoxylpyridine 81 (4.41 g, 40.5 mmol) in toluene (200 mL) at −20° C. was added CbzCl (5.7 ml, 40.5 mmol) in toluene (200 mL) dropwise. After 15 min, ethylmagnesium bromide (23 mL, 2M in THF, 46 mmol) was added dropwise. After 1 hr, 10% aqueous HCl (100 mL) was added and the mixture stirred overnight. The mixture was separated and the organic layer was washed with sat. NaHCO3 and brine. It was dried and concentrated to afford 82 (9 g, 36.4 mmol, 89.9%) that was used directly in the next reaction.

Quelle