反応 #657270

反応方程式

Methyl acetoacetate

Boric acid

3-butyn-1-ol

methyl acetoacetate toluene

→

compound 2

収率 73.0%

but-3-yn-1-yl 3-oxobutanoate

収率 73.0%

溶媒

toluene

反応条件

後処理

1. 1
   温度the mixture was refluxed for 24 hr
2. 2
   その他Solvents were then removed under reduced pressure
3. 3
   その他The crude product was purified by flash column chromatography (SiO2, hexane/ethylacetate:15/1)

実験手順

Methyl acetoacetate (1 g, 8.6 mmol) was dissolved in 40 mL dry toluene. Boric acid (53 mg, 0.86 mmol) and 3-butyn-1-ol (1 g, 14.3 mmol) were added to the methyl acetoacetate/toluene solution under a N2 atmosphere and the mixture was refluxed for 24 hr using a Dean-Stark condenser. Solvents were then removed under reduced pressure. The crude product was purified by flash column chromatography (SiO2, hexane/ethylacetate:15/1) to obtain compound 2 (950 mg, 73% yield), a pale yellow to colorless liquid. 1H NMR 300 MHz (ppm, CDCl3): 4.21 (2H, t J=6.8 Hz), 3.48 (2H, s), 2.59-2.54 (2H, dt J=6.8, 2.7 Hz), 2.29 (3H, s), 2.00 (1H, t J=2.7). 13C NMR (CDCl3, 75 MHz): 200.22, 166.83, 79.70, 70.12, 62.99, 49.92, 30.16, 18.89. ESI-MS: (M+H)+=m/z 155.18 (calculated MW of C8H10O3: 154.16 Da).

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