147489-06-3

586966-54-3

Tert-butyl (4R,6S)-6-[[(1E)-2-cyclopropyl-4-(4-fluorophenyl)-3-quinolinyl]vinyl]-2,2-dimethyl-1,3-dioxane-4-acetate (1.5 kg) was used as raw material and dissolved in acetonitrile (16 L). A mixture of 35% HCl solution (0.91 kg) and purified water (9.5 kg) was slowly added under stirring conditions over a period of 2 hours. Stirring of the reaction mixture was continued for 1 hour. The progress of the reaction was monitored by HPLC and the reaction was terminated after confirming complete consumption of the raw material. The reaction mixture was neutralized with sodium bicarbonate and subsequently extracted with ethyl acetate. The organic layer was separated, washed with sodium chloride solution (1.5 kg) and concentrated under reduced pressure. The concentrated residue was dissolved in ethyl acetate (1.5 L) and hexane (9 L) was slowly added. The mixture was cooled to about 10 °C with continuous stirring for 2 hours. The precipitate was collected by filtration under reduced pressure and dried under reduced pressure at about 50 °C to afford the target product (3R,5S,E)-tert-butyl (3R,5S,E)-7-(2-cyclopropyl-4-(4-fluorophenyl)quinolin-3-yl)-3,5-dihydroxyhept-6-enoate (1.22 kg) as white crystals in 88.4% yield.HPLC purity: 98.555%.