反应详情

2.44 g (5.5 mmol) of methyl 8-(4-benzyloxy-phenyl)-3-methyl-7-oxo-3,7-dihydro-imidazo[4,5-a]quinolizine-10-carboxylate in 50 ml of ethanol were treated with a solution of 1.4 g (21 mmol) of potassium hydroxide (content 86%) in 50 ml of water. After boiling under reflux for 4 hours 200 ml of water were added and the mixture was adjusted to pH 1-2 with 2N hydrochloric acid while cooling with ice. The precipitate obtained was filtered off, washed with water and dried. There were obtained 2.16 g (92%) of 8-(4-benzyloxy-phenyl)-3-methyl-7-oxo-3,7-dihydro-imidazo[4,5-a]quinolizine-10-carboxylic acid as yellow crystals with m.p. 227-229° C.

1. additionwere added
2. temperaturewhile cooling with ice
3. customThe precipitate obtained
4. filtrationwas filtered off
5. washwashed with water
6. customdried