Trimethyl orthobeznoate → 4,8-Dichloro-1-phenyl-[1,2,4]triazolo[4,3-a]quinoxaline

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a 250 ml. three-necked reaction flask equipped with mechanical stirrer and reflux condenser, there were placed 50.0 g. (0.274 mole) of trimethyl orthobenzoate that had been preheated to ca. 70° C. Stirring was commenced and 10.0 g (0.0437 mole) of 2,6-dichloro-3-hydrazinoquinoxaline, the product of Preparation L(a), were added thereto. The resulting reaction mixture was then heated at ca. 120° C., with continued stirring, for a period of 24 hours, followed by cooling to room temperature (~20° C.) and stirring overnight for approximately 16 hours to give a yellow slurry. The latter slurry was then filtered, and the recovered solid product was subsequently washed with two-50 ml. portions of ethanol and air-dried to constant weight to ultimately afford 9.8 g. (72%) of crude 4,8-dichloro-1-phenyl-[1,2,4]triazolo[4,3-a]quinoxaline, m.p. 305°-307° C. Mass Spectrum: m/e, 316/314 (P+).

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