Reference of 21544-81-0, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 21544-81-0, name is 4,6-Dimethoxyindoline-2,3-dione belongs to indolines-derivatives compound, it is a common compound, a new synthetic route is introduced below.
3,5-dimethoxy aniline (199g, 1.30mol) in diethyl ether (5.0 L) was added inthe flask 5L3 Cooled to 0 C. After 45 minutes the HCl gas (227g)introduced into the solution.at 10C 45 Minutes the mixture was filtered, (4L) and washed withisopropyl acetate, under high vacuum, dried at 45 C Night to give the hydrochloride as a white solid (242.3g, 98%). Under stirring the above hydrochloride (20g, 0The mixture.105mol) and oxalyl chloride (33 mL of) isequipped with a reflux condenser, 3-neck flask was heated 2 Hour (170 C externaltemperature), oxalyl chloride was distilled off from the reactionmixture. The flask was cooled to 0 C, was added methanol (40mL). The reactionmixture was heated at reflux for 45 minutes, filtered while hot, with A Alcohol(80mL) and washed to give a yellow-green solid4,6-dimethoxy isatin (17.2g, 79%). After 2 Hour to isatin (162g,0.78mol) was heated in aqueous NaOH solution(40%, 1.5L) in (externalTemperature 70 C) was slowly added to H 2 O 2(35%, 405mL). H 2 O 2 was added after each batch, the internal temperature of the reaction Degree(initially 64 C) increase (to a maximum temperature of 80 C). Afterthe addition was complete, then at 70 C will blister The reaction mixture wasstirred for an additional 2hours, the mixture was stirred overnight while cooling to roomtemperature. The mixtureIt was heated to 70 C. An additional H 2 O 2 (75mL), at 70 C and themixture was stirred for an additional 2 Hours until the reaction was complete.Cooled to 10 C (bath temperature), a solution of Na 2 S 2 O 3 solution (150mL, saturation). The mixture was washed with HCl (37%, 1.6L) was adjusted to pH8, with acetic acid(glacial acetic acid, 75mL) transfer To pH6, while not allowing thereaction mixture was warmed exceed 40 C. The reaction mixture was filtered,washed with water (4L) and washed to give the desired brownsolid amino acid (83.7g, 55%). The amino acid (82.7g, 0.42mol) (4.2L) was added in dry THF EDCl (89.2g, 0.48mol), HOBT(65g, 0.48mol) and NMM (51.3mL), and the mixturewas stirred at roomtemperature for 3 hours. Adding NH3 Aqueoussolution (83mL, 50%), and the mixture was stirred at room temperature for 16 hours.Was added water (1.25L), the The mixture (2 × 250mL) and extracted with DCM.Then the combined extracts were washed with water (2 × 500mL) washed Fandi.Concentrated, slurried with ethyl ether (550mL), filtered, and dried under highvacuum to afford a brown The solid4,6-dimethoxy-2-amino-benzamide (46.7g, 57%).2-Amino-4,6-dimethoxy – benzamide (1.06g, 5.4mmol), 3,5- dimethyl-4-hydroxy Benzaldehyde (0.810g,5.4mmol), K 2 CO 3 (0.747g, 5.4mmol) and I 2(1.645g, 6.5mmol) DMF (20mL) in mixing, at 80 C and the reaction mixture was heated for 12 hours. It was cooledto Room temperature, poured onto crushed ice. The solid was collected, whichwas purified by column chromatography to give a white solid State of 2- (4-hydroxy-3,5-dimethylphenyl)-5,7-dimethoxy-quinazolin -4 (3H) – one (0.9g, 51%). Selected data:MP291-293 C.
The synthetic route of 4,6-Dimethoxyindoline-2,3-dione has been constantly updated, and we look forward to future research findings.
Reference:
Patent; RESVERLOGIX CORP; HANSEN, H; (62 pag.)CN103319408; (2016); B;,
Indoline – Wikipedia,
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