反应详情

One of the intermediates, 2-amino-5-chloropyrazine is prepared following the general procedure of Palamidessi and Bernardi, J. Org. Chem. 29, 2491 (1964), wherein methyl 2-amino-3-pyrazinylcarboxylate is allowed to react with chlorine in acetic acid to yield methyl 2-amino-5-chloro-3-pyrazinylcarboxylate. This ester is hydrolyzed with aqueous sodium hydroxide to yield 2-amino-3-carboxy-5-chloropyrazine, which is then heated in tetrahydronaphthalene and decarboxylated to yield the desired 2-amino-5-chloropyrazine.