Lithium Chloride → 5-Methoxy-2-methyl-benzofuran-7-carboxylic acid methyl ester

Beteiligte Stoffe

Reaktionsschritte

To a solution of 3-allyl-2-hydroxy-5-methoxy-benzoic acid methyl ester (4b) (1.48 g, 6.66 mmol) in DMF (30 mL) was added Cu(OAc)2 (3.63 g, 19.98 mmol), LiCl (847 mg, 19.98 mmol) in H2O (1 mL) and PdCl2 (24 mg, 0.133 mmol). The reaction mixture was stirred at RT for 3 h, quenched with H2O (100 mL) and NH4OH (5 mL) and extracted with EtOAc (100 mL). The organic layer was washed with H2O (100 mL), dried over MgSO4 and concentrated. The residue was purified by flash column chromatograph eluting with 10-15% EtOAc/hexane to give colorless oil (1.48 g, 48%). 1H NMR (400 MHz, CDCl3) δ 7.43 (d, J=2.53 Hz, 1 H) 7.17 (d, J=2.53 Hz, 1 H) 6.36 (s, 1 H) 4.00 (s, 3 H) 3.87 (s, 3 H) 2.51 (s, 3 H)

Herkunft & Nachweise