An Efficient Synthesis of Benzo[ gg ]thiazolo[2,3‐ bb ]quinazolin‐4‐ium and Benzo[ gg ]benzo[4,5]thiazolo[2,3‐ bb ]quinazolin‐14‐ium Hydroxides by a One‐pot, Three‐component Reaction under Green Conditions

摘要

> A new series of benzo[ g ]thiazolo[2,3‐ b ]quinazolin‐4‐ium and benzo[ g ]benzo[4,5]thiazolo[2,3‐ b ]quinazolin‐14‐ium hydroxide derivatives have been synthesized by the one‐pot, three‐component reaction of aryl glyoxal monohydrates, 2‐hydroxy‐1,4‐naphthoquinone, and 2‐aminothiazole or 2‐aminobenzothiazole in the presence of triethylamine and p ‐toluenesulfonic acid as organocatalysts in H ₂ O/acetone (2:1) at room temperature. This method offers mild reaction conditions, excellent yields, easy workup, and readily accessible starting materials and catalysts.