An efficient, transition-metal free and direct C-arylation of 3-hydroxychromone moieties in the presence of a base, air as an oxidant and arylhydrazines as arylating agents to furnish highly biologically active flavonols or 3-hydroxyflavones has been developed. We have further extended our methodology for the C-arylation of the 5-hydroxy pyran-4-one moiety. The role of the free hydroxyl group towards C-arylation has been delineated.

中文翻译：

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羟基定向的C-芳基化：在无过渡金属的条件下合成3-羟基黄酮和2-苯基-3-羟基吡喃-4-酮†

已经开发了在碱，空气作为氧化剂和芳基肼作为芳基化剂的存在下，3-羟基色酮部分的有效，无过渡金属的直接C-芳基化，以提供具有高生物活性的黄酮醇或3-羟基黄酮。我们进一步扩展了用于5-羟基吡喃-4-酮部分的C-芳基化的方法。已经描述了游离羟基对C-芳基化的作用。