반응 #56740

반응 방정식

[(2R)-8-formyl-7-nitro-2,3-dihydro-1,4-benzodioxin-2-yl]methyl 4-methylbenzenesulfonate

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title compound

{7-Nitro-8-[(E)-3-oxo-1-butenyl]-2,3-dihydro-1,4-benzodioxin-2-yl}methyl 4-methylbenzenesulfonate

용매

toluene

반응 조건

후처리

1. 1
   기타precipitated from solution
2. 2
   기타The solvent was removed in vacuum
3. 3
   기타chromatographed on silica gel with methylene chloride as eluent

실험 절차

To a solution of 3.00 g (7.37 mmole) of [(2R)-8-formyl-7-nitro-2,3-dihydro-1,4-benzodioxin-2-yl]methyl 4-methylbenzenesulfonate in 250 mL of toluene was added 2.90 g (9.10 mmole) of 1-triphenylphosphorylidene-2-propanone. The mixture was stirred at room temperature under nitrogen for 5 hours, during which time some product precipitated from solution. The solvent was removed in vacuum and the crude residue was column chromatographed on silica gel with methylene chloride as eluent to give 3.0 g of the (R)-enantiomer of the title compound as a yellow solid. 1H-NMR (CDCl3): doublet 7.8 δ (2 H); doublet 7.6 δ (1 H); doublet 7.5 δ (2 H); doublet 7.4 δ (2 H); doublet 6.95 δ (1 H); doublet 6.6 δ (1 H); multiplet 4.5 δ (1 H); doublet of doublets 4.0 δ (1 H); multiplet 4.2 δ (3 H); singlet 2.45 δ (3 H); singlet 2.4 δ (3 H).

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