1,2-Dimethoxyethane → 5-(5-Tert-butyl-2-hydroxy-phenyl)-furan-2-carbaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A reaction flask was flushed with nitrogen and charged with 2-bromo-4-tert-butyl-phenol (2.019 g, 8.81 mmol), 5-formyl-furan-2-boronic acid (1.831 g, 13.09 mmol) and sodium carbonate (2.783 g, 26.26 mmol). A mixture of 1,2-dimethoxyethane (40 mL) and water (13 mL) was added and the reaction mixture was stirred for 10 min under a nitrogen atmosphere. Dichlorobis(triphenylphosphine) palladium(II) (0.193 g, 0.27 mmol) was added and the mixture was stirred and heated to 65° C. for 17 h. The mixture was cooled to room temperature, diluted with methyl tert-butyl ether (MTBE) (250 mL) and washed successively with 5% aq. potassium carbonate (100 mL), water (100 mL) and brine. The organic layer was separated, dried over sodium sulfate and concentrated under reduced pressure. The residue was chromatographed on flash Silica (100 g, 5 to 10% ethyl acetate in hexanes) to afford 5-(5-tert-butyl-2-hydroxy-phenyl)-furan-2-carbaldehyde (160 mg, 7%). 1H NMR (400 MHz, CDCl3): δ 1.33 (9H, s) 6.51 (1H, bs), 6.90 (1H, d, J=8.8 Hz), 7.03 (1H, d, J=4.0 Hz), 7.32 (1H, dd, J=8.8, 2.4 Hz), 7.36 (1H, d, J=3.6 Hz), 7.73 (1H, d, J=3.2 Hz), 9.64 (1H, s). ESI-MS: 243.0.

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