反応 #70765

反応方程式

CH3CN CO2

4-(2-propyn-1-yl)morpholine

N-methoxy-N-methylacetamide

isopropylmagnesium chloride

→

5-(4-morpholinyl)-3-pentyn-2-one

収率 71.1%

溶媒

THF

THF

THF

反応条件

後処理

1. 1
   workup.ADDITIONwas added dropwise via
2. 2
   workup.STIRRINGThe reaction was stirred for 2 hr (
3. 3
   その他quenched with aq. NH4Cl
4. 4
   抽出extracted with EtOAc
5. 5
   洗浄washed with brine
6. 6
   乾燥dried (Na2SO4)
7. 7
   ろ過filtered
8. 8
   その他The remaining was purified by silica gel chromatography (Analogix
9. 9
   その他evaporated to dryness

実験手順

To a cooled (−40° C., CH3CN/CO2) solution of 4-(2-propyn-1-yl)morpholine (2.2 g, 17.58 mmol) in THF (5 mL) was added dropwise via. syringe under N2 a solution of 2 M isopropylmagnesium chloride in THF (10 mL, 20.00 mmol). The reaction was stirred for 1 hr then a solution of N-methoxy-N-methylacetamide (2.2 mL, 20.69 mmol) in THF (5 mL) was added in one portion. The reaction was stirred for 2 hr (allowed to slowly warm to RT), quenched with aq. NH4Cl, extracted with EtOAc, washed with brine, dried (Na2SO4), filtered and evaoprated to dryness under vacuum. The remaining was purified by silica gel chromatography (Analogix, SF25-60 g, 0 to 80% EtOAc in hexanes). The pure fractions were combined and evaporated to dryness to give the product 5-(4-morpholinyl)-3-pentyn-2-one (2.09 g, 12.50 mmol, 71.1% yield) as a yellow oil. 1H NMR (400 MHz, DMSO-d6) δ 3.62-3.57 (m, 4H), 3.56 (s, 2H), 2.49-2.43 (m, 4H), 2.34 (s, 3H). MS (ES)+m/e 168.0 [M+H]+.

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