Formamide → 4-Chloroquinazoline

Beteiligte Stoffe

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Quinazoline starting materials are commercially available or readily prepared using conventional procedures. For example, 4-hydroxy quinazolines can be prepared from commercially available anthranilic acids via condensation with excess formamide at reflux (M. Endicott et al. J. Am. Chem. Soc., 1946, 68, 1299). Alternatively hydroxy quinazolines can be prepared in dioxane at reflux using Gold's reagent (J. Gupton; Correia, K.; Hertel, G. Synthetic Communications, 1984, 14, 1013). Once in hand, the 4-hydroxy quinazoline is chlorinated under standard conditions, using for example phosphorus pentachloride in phosphorus oxychloride, to provide 4-chloroquinazoline starting materials. The 4-hydroxy quinazoline derivatives can advantageously be chlorinated using the chlorinating reagents and procedure disclosed in U.S. Pat. No. 4,230,644.

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