反应详情

To a solution of 2-methoxy-5-methylphenol (50.0 g, 362 mmol) in CH2Cl2 (1000 mL) at −5° C. were added titanium (IV) chloride (80.0 mL, 724 mmol) slowly via syringe (internal temperature was kept below 0° C. during addition) and dichloromethyl methyl ether (52.9 mL, 593 mmol). After being stirred at room temperature for 3 h, the mixture was poured into ice water. The resulting precipitate was collected by filtration and then washed with EtOAc and Et2O to afford 4-Hydroxy-5-methoxy-2-methylbenzaldehyde. 1H NMR (CDCl3) δ 10.22 (s, 1H), 7.38 (s, 1H), 6.81 (s, 1H), 6.14 (s, 1H), 3.96 (s, 3H), 2.62 (s, 3H); LC/MS: (IE, m/z) (M+1)+=167.0; tR=2.06 min.

1. filtrationThe resulting precipitate was collected by filtration
2. washwashed with EtOAc and Et2O