With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.252990-05-9,Methyl (R)-1-Boc-piperazine-2-carboxylate,as a common compound, the synthetic route is as follows.
(R)-Piperazine-1,2-dicarboxylic acid 1-tert-butyl ester 2-methyl ester (120 mg, 0.49 mmol) and 2-Bromo-5-trifluoromethyl-pyridine (133 mg, 0.59 mmol) were dissolved into 2.0 mL of anhydrous toluene (degassed). In a separate, septum-equipped vial were placed tri(dibenzylideneacetone)dipalladium (0) (22 mg, 0.024 mmol), 1,3-bis(2,6-di-i-propylphenyl)imidazolium chloride (42 mg, 0.1 mmol) and sodium t-butoxide (57 mg, 0.59 mmol). This “catalytic” vial was equipped with a magnetic stir bar and flushed with dry nitrogen. The reactant solution was next transferred to the “catalytic” vial and the mixture was stirred at 100 C. for 5 h. After this period the mixture was combined with 20 mL of hexane/EtOAc (2:1) and was passed through a pad of Celite. The resulting filtrate was evaporated in vacuo and purified using flash silica chromatography (0-20% EtOAc/Hexane) to yield 110 mg (58%) of (R)-4-(5-Trifluoromethyl-pyridin-2-yl)-piperazine-1,2-dicarboxylic acid 1-tert-butyl ester 2-methyl ester, intermediate IX-B, as a yellow residue. 1H NMR (400 MHz, CDCl3) delta 8.39-8.38 (m, 1H), 7.65 (d, 1H), 6.68 (m, 1H), 4.89-4.68 (m, 2H), 4.29 (dd, 1H), 3.95 (dd, 1H), 3.69 (s, 3H), 3.43-3.26 (m, 2H), 3.12-2.97 (m, 1H), 1.51-1.46 (m, 9H)., 252990-05-9
The synthetic route of 252990-05-9 has been constantly updated, and we look forward to future research findings.
Reference：
Patent; Kalypsys, Inc.; US2005/234046; (2005); A1;,
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