Electric Literature of 4774-14-5, 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. 4774-14-5 name is 2,6-Dichloropyrazine, 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.
Compound 5-5 was prepared using 3,5-dichloro-2-methylpyrazine and l-boc-4- hydroxypiperidine in Step 3.; 3 ,5-dichloro-2-methylpyrazine; To a solution of n-butyl lithium (1.6M in hexanes; 29 mL, 47 mmol) in tetrahydrofuran (200 mL) at -30C was added 2,2,6,6-tetramethylpiperidine (8.6 mL, 50 mmol). This solution was allowed to warm to 00C over 20 minutes then cooled to -78C. To this solution was added a solution of 2,6-dichloropyrazine (5 g, 34 mmol) in tetrahydrofuran (200 mL) dropwise via cannula. After 30 minutes, iodomethane (21 mL, 340 mmoL) was added. After 1 h, the reaction mixture was quenched with a mixture of EtOH (25 mL), THF (25 mL) and IN aqueous HCl (5 mL). The reaction mixture was allowed to warm to room temperature then concentrated to a crude oil. The crude oil was partitioned between water (500 mL) and CH2Cl2 (500 mL). The organic layer was washed with brine (250 mL). The first aqueous layer was back-extracted with CH2Cl2 (500 mL). The combined organic layers were dried over sodium sulfate, filtered and concentrated. The crude residue was purified by silica gel chromatography (EtOAc/Hexanes gradient) to afford 3,5-dichloro-2-methylpyrazine as a yellow oil. LRMS (ESI) calculated for C5H4Cl2N2 [M+H]+, 163.0; found 163.1.
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2,6-Dichloropyrazine, and friends who are interested can also refer to it.
Reference:
Patent; MERCK & CO., INC.; WO2009/54941; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem