4-[(2,2-Dimethyl-4,6-dioxo- [1,3]dioxan-5-ylidenem

The starting material was prepared as follows: Methyl 4-amino-2-methoxy-benzoate (1.07 g) and 5-methoxymethylene-2, 2-dimethyl-[1, 3]dioxan-4, 6-dione (1.0 g) were dissolved in 2-propanol (20 ml), and the mixture was stirred at 70°C for one hr. The solvent was removed by distillation under the reduced pressure, and the residue was washed with ether to give methyl 4-[(2, 2-dimethyl-4, 6-dioxo-[1, 3]dioxan-5-ylidenemethyl)-amino]-2-methoxy-benzoate (1.71 g, yield 95percent). Methyl 4-[(2, 2-dimethyl-4, 6-dioxo-[1, 3]dioxan-5-ylidenemethyl)-amino ]-2-methoxy-benzoate (1.70 g) and biphenyl (4.76 g) were suspended in diphenyl ether (15 ml), and the suspension was stirred at 240°C for one hr. The suspension was cooled to room temperature, and the precipitated crystal was collected by filtration and was washed with ether. The crystal thus obtained as such was used in the next reaction without further purification. N, N-Dimethylformamide (2 drops) was added to the crystal thus obtained. Further, phosphorus oxychloride (2.5 ml) was added thereto, and the mixture was stirred at 100°C for 2 hr. The solvent was removed by distillation under the reduced pressure, and water was added to the residue under ice cooling. The aqueous layer was neutralized with an aqueous sodium hydrogencarbonate solution, and the organic layer was extracted with ethyl acetate. The ethyl acetate layer was washed with water and was dried over anhydrous sodium sulfate. The solvent was removed by distillation under the reduced pressure, and the residue was purified by thin layer chromatography with a methanol-chloroform system to give methyl 4-chloro-7-methoxy-quinoline-6-carboxylate (707 mg, yield 55percent) (2 steps).Methyl 2-methoxy-4-amino-benzoate (500.00 g, 2.76 mol), 2, 2-dimethyl-1, 3-dioxane-4, 6-dione (397.73 g, 2.76 mol) and trimethyl orthoformate (292.84 g, 2.76 mol) were added to isopropanol (5.00 L). The reaction solution was heated up to an outer temperature of 90 °C and kept refluxing for 1 hour. The completion of the reaction was detected by TLC. The reaction solution was cooled to an outer temperature of 20 °C in an ice bath and then filtered. The solid was washed with MTBE (300 ml * 2) and then concentrated to dryness in a water bath. Compound 1A (873.00 g, 2.47 mol, the yield was 89.62percent and the purity was 95percent) was obtained as a light red powder. NMR (DMSO) demonstrated that the product was correct.

Molecular Weight:335.31
XLogP3:2.3
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:8
Rotatable Bond Count:5
Exact Mass:335.10050188
Monoisotopic Mass:335.10050188
Topological Polar Surface Area:100
Heavy Atom Count:24
Complexity:533
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes