Category: 143673-66-9piperazines

With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.143673-66-9,(R)-3-Isopropylpiperazine-2,5-dione,as a common compound, the synthetic route is as follows.

Step A: Preparation of (R)-2-isopropyl-3,6-dimethoxy-2,5-dihydropyrazine (1): To a 2 L round-bottomed flask were added (R)-3-isopropylpiperazine-2,5-dione (20.7 g, 133 mmol), Me3OBF4 (49.0 g, 331 mmol) and CH2Cl2 (500 mL). The slurry was stirred vigorously at room temperature under nitrogen atmosphere. After stirring 18 hours, the slurry became a clear solution with very viscous yellow oil settling on the bottom of the flask. An additional equivalent of Me3OBF4 (19.6 g, 133 mmol) was added and the mixture was stirred at room temperature. After 23 hours, the mixture was cooled in an ice bath, and 200 g of ice and 100 mL of concentrated ammonium hydroxide solution (28%) were added to the reaction mixture. The reaction mixture was stirred in an ice bath for 1 hour. The layers were separated and aqueous layer was extracted with CH2Cl2 (2*50 mL). The combined organic layers were washed with saturated NaHCO3 solution (2*100 mL) and brine (100 mL), dried over K2CO3, filtered through a Celite pad, and concentrated under reduced pressure to provide 25.9 g of light brown oil. The crude material was purified by chromatography with 1:4 ether/pentane to provide 17.464 g of compound 1 as a colorless oil (71.5% yield). 1H NMR (400 MHz, CDCl3) delta 4.08-3.94 (m, 3H), 2.95 (s, 3H), 2.87 (s, 3H), 2.30-2.18 (m, 1H), 1.04 (d, J=7.03 Hz, 3H), 0.76 (d, J=6.64 Hz, 3H).

143673-66-9, 143673-66-9 (R)-3-Isopropylpiperazine-2,5-dione 736000, apiperazines compound, is more and more widely used in various fields.

Reference£º
Patent; ARRAY BIOPHARMA INC.; US2006/264431; (2006); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

143673-66-9, (R)-3-Isopropylpiperazine-2,5-dione is a piperazines compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

[0561] To a solution of compound 4-01-4 (11 g, 70 mmol) in dichloromethane (500 mL) was added trimethyloxonium tetrafiuorob orate (41.7 g, 282 mmol). The slurry was stirred vigorously at 20C under a nitrogen atmosphere for 18 hours. The slurry became a clear solution with very viscous yellow oil settled on the bottom of the flask, then another 10.4 g (70 mmol) of trimethyloxonium tetrafiuorob orate was added and the mixture was stirred at 20C for 24 hours. The mixture was cooled in an ice bath, and 200 g of ice and 100 mL of concentrated ammonium hydroxide solution (30%) were added. The reaction mixture was stirred in an ice bath for 1 hour. The layers were separated and aqueous layer was extracted with DCM (500 mL*2). The combined organic layers were washed with saturated sodium bicarbonate solution (300 mL *2) and brine (300 mL), dried over anhydrous sodium sulfate, filtered through a celite pad, and concentrated under reduced pressure. The residue was purified by column chromatography (petroleum ether to petroleum ether: ethyl acetate = 10: 1) to afford compound 4-01-5 (9 g, 69% yield) as yellow oil.

143673-66-9, As the paragraph descriping shows that 143673-66-9 is playing an increasingly important role.

Reference£º
Patent; CORNELL UNIVERSITY; TRI-INSTITUTIONAL THERAPEUTICS DISCOVERY INSTITUTE; LIN, Gang; NATHAN, Carl; KIRKMAN, Laura; ZHAN, Wenhu; MORGAN, Trevor; SATO, Kenjiro; HARA, Ryoma; KAWASAKI, Masanori; IMAEDA, Toshihiro; TOITA, Akinori; OKAMOTO, Rei; YUKAWA, Takafumi; ASO, Kazuyoshi; WONG, Tzu-Tshin; GINN, John, D.; FOLEY, Michael, A.; (296 pag.)WO2019/75259; (2019); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics