With the rapid development and complex challenges of chemical substances, the synthesis of new drugs is usually one of the most effective ways to increase yield.55405-67-9, name is 3-Bromopyrazolo[1,5-a]pyrimidine, molecular formula is C6H4BrN3, molecular weight is 198.0201, as common compound, the synthetic route is as follows.COA of Formula: C6H4BrN3
A solution of 3-bromopyrazolo[1,5-ajpyrimidine (0.04 g, 0.202 mmol), (8)- tert-butyl (2,4-dimethyl- 1 -(4-(4,4,5,5-tetramethyl- 1,3 ,2-dioxaborolan-2-yl)-2- (trifluoromethyl)phenoxy)pentan-2-yl)carbamate (prepared as described in Example 255, Parts A and B) (0.122 g, 0.242 mmol), and potassium phosphate tribasic (0.106 g, 0.606 mmol) in THF (5 mL) and water (0.5 mL) was purged with nitrogen gas for30 mi XPhos generation precatalyst (9.37 mg, 0.030 mmol) was added to the reaction mixture and the solution was purged with nitrogen gas again for 10 mm. The reaction mixture was heated at 80C for 12 h. The reaction mixture was concentrated and the residue obtained was dissolved in ethyl acetate (30 mL) and water (30 mL). The biphasic mixture was filtered through diatomaceous earth andthe diatomaceous earth was washed with ethyl acetate (50 mL). The ethyl acetate layer was separated, dried over Na2SO4, filtered, and concentrated under reduced pressure to afford (S)-tert-butyl (2,4-dimethyl-1-(4-(pyrazolo[1,5-ajpyrimidin-3-yl)- 2-(trifluoromethyl)phenoxy)pentan-2-yl)carbamate (50 mg, 0.102 mmol, 50% yield) as a brown solid which was carried forward without further purification. LCMS(ESI) m/e 493.3 [(M+H), calcd for C25H32F3N403 493.21; LC/MS retention time (Method Al): tR = 1.83 mm.
At the same time, in my other blogs, there are other synthetic methods of this type of compound,55405-67-9, 3-Bromopyrazolo[1,5-a]pyrimidine, and friends who are interested can also refer to it.
Reference:
Patent; BRISTOL-MYERS SQUIBB COMPANY; BRONSON, Joanne J.; CHEN, Ling; DITTA, Jonathan L.; DZIERBA, Carolyn Diane; JALAGAM, Prasada Rao; LUO, Guanglin; MACOR, John E.; MAISHAL, Tarun Kumar; NARA, Susheel Jethanand; RAJAMANI, Ramkumar; SISTLA, Ramesh Kumar; THANGAVEL, Soodamani; (318 pag.)WO2017/59080; (2017); A1;,
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia