Water → HCID 15341855, compound

Participants

Reaction Steps

12.9 g (34.8 mmol) (E)-3-carboethoxy-4-(2'-bromo-5'-isopropylphenyl)-3-butenic acid (3) were dissolved in 340 acetic anhydride and heated for 6 h in reflux. After cooling to room temperature, a solution of 200 g ice, 200 g water and 90 g K2CO3 were added. After extraction with dichloromethane, the combined organic layers were dried (MgSO4), filtered and concentrated under reduced pressure. The dried residue was dissolved in a solution of 8.40 g (389 mmol) sodium in 300 mL dry ethanol and stirred for 4 h at room temperature under Ar. The solvent was removed in vacuo and the residue was partitioned between 100 mL dichloromethane and 30 mL 2N HCl-solution. The organic phases were collected, dried (MgSO4) and concentrated under reduced pressure. The residue was recrystallized from isopropanol to give 11.7 g (95%) ethyl-8-bromo-4-hydroxy-5-isopropoxy-2-naphthoate as yellow crystals (m.p. 106° C.).

Provenance & Evidence