反应详情

A trifluoroacetic acid (25 ml) solution of 3-carbomethoxy-5-chloro-2-hydroxyphenylacetaldehyde (5c) (5.20 g, 22.7 mmol) was refluxed for 2 hours under argon, and then poured into saturated Na2CO3. The resulting precipitate was collected by filtration, and then purified by column chromatography (100% CH2Cl2) to give 6c as a cream colored solid (3.02 g, 63.2% yield). Analytical sample was prepared by recrystallization from ethyl ether, mp 144°-145° C. IR (nujol) 1710 (ester) cm-1. NMR (CDCl3) δ 7.87-6.70 (m, 4H, aromatic protons) and 4.0 (s, 3H, CH3).

1. filtrationThe resulting precipitate was collected by filtration
2. custompurified by column chromatography (100% CH2Cl2)