1,1-Dibromoethane → 2,3-Dihydro-1,4-benzodioxine-5-carbaldehyde

Beteiligte Stoffe

Reaktionsschritte

2,3-Dihydroxybenzaldehyde (58 g, 420 mmol) was added to a refluxing mixture of dibromoethane (107.4 g, 570 mmol), sodium hydroxide (35.7 g, 890 mmol) and tetrabutyl ammonium bromide (3 g) in water (50 mL). After heating at reflux for 4 h, the mixture was cooled and the organic layer separated, washed with base, dried over sodium sulfate and concentrated in vacuo. The residue was Kugelrohr distilled at 135° to give the product (48 g, 70%) which solidified on standing (mp 61°-62° C.). Anal. Calc'd: C, 65.85; H, 4.91; Found: C, 65.73; H, 4.86.

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