Reaktion #74602

Reaktionsgleichung

2-bromo-1-methoxy-4-(trifluoromethyl)benzene

tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydropyridine-1(2H)-carboxylate

potassium carbonate

dichloromethane

→

title compound

tert-Butyl 4-[2-methoxy-5-(trifluoromethyl)phenyl]-3,6-dihydropyridine-1(2H)-carboxylate

Lösungsmittel

N,N-dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas purged with argon
2. 2
   Temperaturbefore cooling to room temperature
3. 3
   Filtrationfiltering through Celite™
4. 4
   Waschenwashing with ethyl acetate
5. 5
   EinengenThe filtrate was concentrated in vacuo to ˜quarter
6. 6
   Sonstigepartitioned between water (100 mL) and ethyl acetate (75 mL)
7. 7
   ExtraktionThe aqueous layer was extracted with ethyl acetate (2×75 mL)
8. 8
   WaschenCombined organic layers were washed with water, aqueous lithium chloride solution, saturated aqueous sodium chloride solution
9. 9
   Trocknendried over sodium sulfate
10. 10
    Filtrationfiltered
11. 11
    Einengenconcentrated in vacuo
12. 12
    SonstigeThe residue was purified by automated flash chromatography (24 g silica gel)
13. 13
    Wascheneluting with hexanes

Vorschrift

A suspension of 2-bromo-1-methoxy-4-(trifluoromethyl)benzene (825 mg, 3.23 mmol), tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydropyridine-1(2H)-carboxylate (1.00 g, 3.23 mmol), potassium carbonate (1.34 g, 9.697 mmol) and [1,1-bis(diphenylphosphino)ferrocene]dichloro-palladium(11) complex with dichloromethane (1:1) (158 mg, 0.193 mmol) in N,N-dimethylformamide (19 mL) was purged with argon. After 30 minutes, the reaction mixture was heated at 90° C. and stirred for 22 hours before cooling to room temperature and filtering through Celite™, washing with ethyl acetate. The filtrate was concentrated in vacuo to ˜quarter and partitioned between water (100 mL) and ethyl acetate (75 mL). The aqueous layer was extracted with ethyl acetate (2×75 mL). Combined organic layers were washed with water, aqueous lithium chloride solution, saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by automated flash chromatography (24 g silica gel) eluting with hexanes:ethyl acetate (gradient 1:0 to 3:1, by volume) to afford the title compound as a clear oil, 1.1 g.

Quelle