Process for preparation of 2-(6-nitropyridin-3-yl)-9H-dipyrido2,3-b;3',4'-dpyrrole

摘要

A process for preparing the compound of formula I; ;comprising:a) coupling a compound of formula 2; ;wherein a leaving group O—SO₂—R is selected from the triflate group, the tosylate group, the mesylate group, the besylate group, the nosylate group or the brosylate group,with a suitable boronic acid, a trifluoroborate or a boronic acid esterunder argon condition and in the presence of a catalyst and a base in a suitable solvent and then isolating the product as an acid addition saltto afford the compound of formula Ia; ;andb) converting the acid addition salt of formula Iawherein the acid HX comprises suitable organic or inorganic acids into the compound of formula I; ;by treatment with at least a stoichiometric equivalent of a suitable base.