反応 #56739

反応方程式

{(2R)-7-nitro-8-[3-oxo-1-propenyl]-2,3-dihydro-1,4-benzodioxin-2-yl}methyl 4-methylbenzenesulfonate

water

→

title compound

2,3-Dihydro[1,4]dioxino[2,3-f]quinolin-2-ylmethyl 4-methylbenzenesulfonate

溶媒

acetic acid ethanol

反応条件

後処理

1. 1
   温度the mixture was heated
2. 2
   温度at reflux under nitrogen for 8 hours
3. 3
   ろ過the mixture filtered through a pad of celite
4. 4
   抽出extracted with ethyl acetate
5. 5
   乾燥The extract was dried over magnesium sulfate
6. 6
   ろ過filtered
7. 7
   その他evaporated in vacuum
8. 8
   その他chromatographed on silica gel using a gradient elution commencing with 20% ethyl acetate/hexane

実験手順

To a solution of {(2R)-7-nitro-8-[3-oxo-1-propenyl]-2,3-dihydro-1,4-benzodioxin-2-yl}methyl 4-methylbenzenesulfonate (3.50 g, 8.35 mmole) in 200 mL of acetic acid/ethanol (1:1) was added 2.35 g (42.1 mmole) of iron powder and the mixture was heated at reflux under nitrogen for 8 hours. After the reaction was complete, 150 mL of water was added and the mixture filtered through a pad of celite. The filtrate was neutralized with saturated sodium bicarbonate and extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and evaporated in vacuum. The residue was column chromatographed on silica gel using a gradient elution commencing with 20% ethyl acetate/hexane and ending with 70% ethyl acetate/hexane to give 1.85 g of the (R)-enantiomer of the title compound as a yellow oil. 1H-NMR (CDCl3): doublet 8.8 δ (1 H); doublet: 8.2 δ (1 H); doublet 7.8 δ (2 H); doublet 7.6 δ (1 H); multiplet 7.35 δ (1 H); multiplet 7.25 δ (3 H); multiplet 4.6 δ (1 H); multiplet 4.3-4.4 δ (3 H); multiplet 4.2 δ (1 H); singlet 2.4 δ (3 H).

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