反应详情

A solution of 0.54 g (0.67 mmole) of (2R)-2,3,8,9-tetrahydrofuro[3,2-f][1,4]benzodioxin-2-ylmethyl 4-methylbenzenesulfonate and 0.46 g (2.0 mmole) of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in 20 ml of benzene was refluxed under nitrogen for 15 hours. The solvent was removed in vacuum and the residue column chromatographed on silica gel with methylene chloride as eluant. The product fractions were combined and concentrated in vacuum to give 0.40 g of the (R)-enantiomer of the of the title compound as a tan solid. 1H-NMR (CDCl3): doublet 7.8 δ (2H); doublet 7.52 δ (1H); doublet 7.3 δ (2H); doublet 6.95 δ (1H); doublet 6.8 δ (1H); doublet 6.65 δ (1H); multiplet 4.5 δ (1H); multiplet 4.25 δ (3H); doublet of doublets 4.1 δ (1H); singlet 2.4 δ (3H).

1. customThe solvent was removed in vacuum
2. customthe residue column chromatographed on silica gel with methylene chloride as eluant
3. concentrationconcentrated in vacuum