Application of 5521-55-1, 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. 5521-55-1 name is 5-Methylpyrazine-2-carboxylic acid, 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.
To a flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added 5-methylpyrazine-2-carboxylic acid (1.0 eq), tert-butanol (3.5 vols) and di-isopropylethylamine (1.5 eq) under a nitrogen atmosphere. The mixture was heated to 82 C., then diphenylphosphorylazide (1.0 eq) was added over a time period of 5-14 hours, maintaining the temperature of the reaction mixture at approximately 82 C. The reaction mixture was stirred for at least 1.5 hours, and then cooled to approximately 60 C. A solution of 4% w/w sodium hydroxide (1.75 eq) was added over a period of 2 hours. The mixture was cooled to 15 C. over at least 5 hours then held at 15 C. for 3 hours. The batch was then filtered, and the solid slurry washed with water (2 vols). The batch was again slurry washed with water (2 vols). After drying at 55-60 C. overnight, the desired product was obtained as a solid (corrected yield 56-63%). 1H NMR delta (400 MHz CDCl3): 9.18 (s, 1H), 8.17 (bs, 1H), 8.11 (s, 1H), 2.51 (s, 3H), 1.56 (s, 9H)
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 5-Methylpyrazine-2-carboxylic acid, and friends who are interested can also refer to it.
Reference:
Patent; AstraZeneca AB; US2010/210841; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem