A common heterocyclic compound, 764667-64-3, name is 5-(1-Hydroxy-2-(2,4,5-trifluorophenyl)ethylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione, molecular formula is C14H11F3O5, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. 764667-64-3.
2,4, 5-TRIFLUOROPHENYLACETIC acid (2-1) (150 g, 0.789 mol), Meldrum’s acid (125 g, 0. 868 mol), and 4- (DIMETHYLAMINO) pyridine (DMAP) (7.7 g, 0063 mol) were charged into a 5 L three-neck flask. N, N-DIMETHYLACETAMIDE (DMAC) (525 ML) was added in one portion at room temperature to dissolve the solids. N, N-diisopropylethylamine (282 ML, 1.62 mol) was added in one portion at room temperature while maintaining the temperature below 40 C. Pivaloyl chloride (107 ML, 0.868 mol) was added dropwise over 1 to 2 h while maintaining the temperature between 0 and 5 C. The reaction mixture was aged at 5 C for 1 h. Triazole hydrochloride 1-4 (180 g, 0.789 mol) was added in one portion at 40-50 C. The reaction solution was aged at 70 C for several h. 5% Aqueous sodium hydrogencarbonate solution (625 ML) was then added dropwise at 20-45 C. The batch was seeded and aged at 20-30 C for 1-2 h. Then an additional 525 mL of 5% aqueous sodium hydrogencarbonate solution was added dropwise over 2-3 h. After aging several h at room temperature, the slurry was cooled to 0-5 C and aged 1 h before filtering the solid. The wet cake was displacement-washed with 20% aqueous DMAC (300 mL), followed by an additional two batches of 20% aqueous DMAC (400 mL), and finally water (400 mL). The cake was suction-dried at room temperature. The isolated yield of final product 2-3 was 89%.
The synthetic route of 5-(1-Hydroxy-2-(2,4,5-trifluorophenyl)ethylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione has been constantly updated, and we look forward to future research findings.
Reference:
Patent; MERCK & CO., INC.; WO2005/20920; (2005); A2;,
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