Extracurricular laboratory: Synthetic route of 5521-55-1

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.

Electric Literature 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.

Step 1: To a solution of 2-methylpyrazine-5-carboxylic acid (10 g, 72.4 mmol) and TEA (20 mL, 108 mmol) in t-butanol (156 mL) and dioxanes (100 mL) was added diphenyl phosphorylazide (23.4 mL, 108 mmol) and the resulting solution was warmed at 100 C. for 3 hours and then cooled to room temperature overnight. The crude reaction mixture was concentrated in vacuo. Purification by chromatography (silica 0-15% ethyl acetate/hexanes) following trituration of impure fractions with ether afforded (5-methyl-pyrazin-2-yl)-carbamic acid tert-butyl ester (10.6 g, 70%): 1H NMR (300 MHz, CHLOROFORM-d) delta ppm 1.56 (s, 9H) 2.51 (s, 3H) 8.02 (br. s., 1H) 8.07-8.14 (m, 1H) 9.18 (d, J=1.13 Hz, 1H).

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; Brotherton-Pleiss, Christine E.; Walker, Keith A. M.; US2012/149718; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem