2-Chloro-5,6-diphenylpyrazine is a diphenylpyrazine derivative used in a study to determine a novel class of prostacyclin receptor agonists.
5-chloro-2,3-diphenylpyrazine is an intermediate of Selexipag, a medication used to treat pulmonary arterial hypertension (PAH).
50 gm of 2-hydroxy-5,6-diphenylpyrazine obtained was treated with 250 ml of POCI3 and then heated the reaction mixture at 100-110 °C with stirring for 5-6 hrs. The reaction mixture was cooled to room temperature and poured in 1000 ml of ice water at 0-5 °C and maintained with stirring for 60 minutes. The solid obtained was filtered, washed with water and dried to obtain 41.3 gm of 5-chloro-2,3-diphenylpyrazine. Yield: 77.00 percent.
[1] Journal of the American Chemical Society, 1952, vol. 74, p. 1580,1582
[2] Patent: WO2017/168401, 2017, A1. Location in patent: Page/Page column 12