Sodium Hydroxide → 7-Diethylaminocoumarin-3-carboxylic acid

Participants

Reaction Steps

--A solution of the ester 1 (11.6g, 40 mmol) in MeOH (100 ml) was heated under reflux and 0.5 M aq. NaOH (100 ml) was added rapidly. A yellow solid precipitated within 5 min and the mixture was cooled and acidified with 2 M aq. HCl to give an orange solid which was filtered and washed with 2 M aq. HCl, then with water until neutral and finally with MeOH (50 ml), and dried in vacuo to give the acid 2 (9.4 g) A sample recrystallised from MeOH-diisopropyl ether as orange laths, m.p. 231-232° C. (lit. m.p. 227-229° C. see U.S. Pat. No. 4,317,774).

Provenance & Evidence