Water → HCID 14423300, compound

Participants

Reaction Steps

Reflux 6,8,9,10-tetrahydro-5',5'-dimethyl-10-phenyl-spiro[benzo[b][1,8]naphthyridin-7-(5H),2'-[1,3]dioxan]-5-one (32 mmoles) with water (6 ml) and p-toluenesulfonic acid monohydrate (3.2 g) dissolved in 2-butanone (319 ml) for 3 days. Monitor the progress of hydrolysis by thin-layer chromatography. When hydrolysis is complete, cool the solution and evaporate the 2-butanone. Wash a CH2Cl2 solution of the residue with aqueous NaHCO3 solution and with water. Evaporate the CH2Cl2 after drying the organic solution, and crystallize the residue from C2H5OH--CHCl3 to obtain 6,8,9,10-tetrahydro-10-phenyl-benzo[b][1,8]naphthyridin-5,7-dione, m.p. 244°-247° C. (d).

Provenance & Evidence