Реакция #70565

Уравнение реакции

ammonium chloride

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

CO2

Methylmagnesium chloride

→

title compound

Выход 78.0%

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

Выход 78.0%

Растворители

diethyl ether

ethanol

THF

Условия реакции

Обработка

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

Методика

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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