Reference of 346-34-9, 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. 346-34-9, name is 4-Fluoroindoline-2,3-dione belongs to indolines-derivatives compound, it is a common compound, a new synthetic route is introduced below.
Intermediate 1 A6-bromo-2-(trifluoromethyl)quinoline-4-carboxylic acid 300 mg (1.33 mmol) of 5-bromo-1 H-indole-2,3-dione was suspended in 3 mL water in a microwave vial. 82 mg ( 1.46 mmol) potassium hydroxide, 152 muL (2.65 mmol) acetic acid and 152 mg (1.86 mmol) sodium acetate were added so that the pH was around 5. The solution was cooled to 10 C and 238 muL (2.65 mmol) 1 ,1,1 -trifluoroacetone was added rapidly, the microwave vial was sealed and heated in the microwave for 2 h at 120 C. The reaction was stopped by the addition of 10% aqueous hydrochloric acid solution and the resulting precipitate was isolated by filtration, washed with water and dried in a vacuum drying cabinet at 50 C overnight to obtain 409 mg (1.28 mmol, 96%) of the desired title compound .In analogy to intermediate 1 A, 300 mg (1.82 mmol) 4-fluoro-1 H-indole-2,3-dione was heated with 900 muL (9.08 mmol) 1 -cyclopropylethanone, 112 mg (2.00 mmol) potassium hydroxide, 208 muL (3.63 mmol) acetic acid and 209 mg (2.54 mmol) sodium acetate in 3 mL water for 6 h at 150 C in the microwave. The reaction mixture was quenched with 10% hydrochloric acid solution and filtered. The filtrate was extracted with ethyl acetate and the combined organic layers were washed with brine, dried over sodium sulfate, filtered and evaporated to obtain 120 mg (0.52 mmol, 29%) of the desired title compound after drying.1 H NMR (400 MHz, DMSO d6): delta (ppm) = 1.10 – 1.17 (m, 4 H), 2.40 – 2.47 (m, 1 H), 7.52 – 7.60 (m, 2 H), 7.93 (s, 1 H), 8.35 – 8.41 (m, 1 H,) 13.98 (br. s, 1 H).
In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 4-Fluoroindoline-2,3-dione, other downstream synthetic routes, hurry up and to see.
Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; HEISLER, Iring; MUeLLER, Thomas; SIEBENEICHER, Holger; BUCHMANN, Bernd; CLEVE, Arwed; GUeNTHER, Judith; KOPPITZ, Marcus; HEROULT, Melanie; NEUHAUS, Roland; PETRUL, Heike; QUANZ-SCHOeFFEL, Maria; WO2015/91428; (2015); A1;,
Indoline – Wikipedia,
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