Reaktion #70565

Reaktionsgleichung

ammonium chloride

N-methoxy-N-methyl-2-phenylpyrimidine-5-carboxamide

CO2

Methylmagnesium chloride

→

title compound

Ausbeute 78.0%

1-(2-phenylpyrimidin-5-yl)ethanone

Ausbeute 78.0%

Lösungsmittel

diethyl ether

ethanol

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto warm to room temperature over one hour
2. 2
   SonstigeThe crude reaction mixture
3. 3
   workup.ADDITIONwas then poured into a separatory funnel that
4. 4
   SonstigeThe organic layer was separated
5. 5
   Waschenthe aqueous layer was washed again with diethyl ether (100 mL)
6. 6
   TrocknenThe combined organic layer was dried over anhydrous sodium sulfate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated under reduced pressure
9. 9
   Sonstigeto afford a white solid as the crude product
10. 10
    SonstigeThe crude solid was triturated with a hexane-ethyl acetate (9:1 v/v) mixture (20 mL)
11. 11
    FiltrationThe precipitate in solution was filtered

Vorschrift

A solution consisting of N-methoxy-N-methyl-2-phenylpyrimidine-5-carboxamide (Step I, 1.80 g, 7.39 mmol) in anhydrous THF (20 mL) was cooled in a −60° C. bath (ethanol, CO2(s)). Methylmagnesium chloride (Aldrich, 3.0 M in THF, 2.75 mL, 8.14 mmol) was subsequently added dropwise to the reaction mixture. The reaction mixture was stirred for 30 minutes in the −60° C. bath and was subsequently allowed to warm to room temperature over one hour. The crude reaction mixture was then poured into a separatory funnel that contained diethyl ether (200 mL) and saturated ammonium chloride (150 mL). The organic layer was separated and the aqueous layer was washed again with diethyl ether (100 mL). The combined organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to afford a white solid as the crude product. The crude solid was triturated with a hexane-ethyl acetate (9:1 v/v) mixture (20 mL). The precipitate in solution was filtered to afford the title compound as a white solid (1.15 g, 78% yield); Rf 0.72 with 1:1 v/v hexanes-ethyl acetate; 1H-NMR (400 MHz; CDCl3) δ 9.25 (s, 2H), 8.53 (dd, 2H), 7.58 (m, 3H), 2.63 (s, 3H); MS (APCI+) m/z 199.0 (M+1).

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