Electric Literature of 875781-43-4, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 875781-43-4 name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.
Step 1To a 500 ml three necked round bottom flask, 2-bromo-5H-pyrrolo[2,3-b]pyrazine (5.0 g,0.0252 mole) was taken in CH2C12 (150 ml). The reaction mixture was cooled to 0 C and diethylaluminiumchloride (1M solution in hexanes) (9.11 g, 0.0756 mole) was added drop wise at the same temperature under nitrogen atmosphere. The reaction mixture was stirred for 30 min at 0 C followed by slow addition of pivoloyl chloride (29.45 g, 0.2444 mole) over 15min at the same temperature. After completion of the addition, the reaction mixture was warmed up to RT Attorney Docket No. 11913-1008 and then up to 40 C and stirred for 16 hrs. The completion of the reaction was monitored on TLC using hexanes: ethyl acetate (5:5) as a mobile phase. After completion of the reaction, the reaction mixture was poured in saturated NaHC03 solution with stirring at 10 C, diluted with CH2C12 and filtered through high flow. The filtrate was collected and washed with brine solution. Layers were separated and the aq. Layer was extracted with CH2C12. The combined organic layer was dried over Na2S04, filtered and concentrated to afford crude product which was subjected for the column purification. The crude compound was purified using column purification by eluting the compound with 10 -25% ethyl acetate in hexanes to yield 5.3g of l-(2- bromo-5H-pyrrolo[2,3-b] pyrazine-7-yl)- 2,2-dimethyl propan-l-one
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, and friends who are interested can also refer to it.
Reference:
Patent; PRINCIPIA BIOPHARMA INC.; GOLDSTEIN, David Michael; BRAMELD, Kenneth Albert; VERNER, Erik; WO2012/158785; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem