Catalyzed by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)/tert-butyl nitrite (TBN)/O2, an efficient tandem oxidative reaction of uracils/thiouracil with 1,3-diarylpropenes is disclosed. It undergoes oxidative coupling, intramolecular cyclization, and dehydro-aromatization to provide multi-substituted pyrido[2,3-d]pyrimidines/thiopyrido[2,3-d]pyrimidines in moderate to excellent yields. It has the advantages of high atom economy, green terminal oxidant, and metal-free conditions.

中文翻译：

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2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)/亚硝酸叔丁酯(TBN)/O2催化合成吡啶并[2,3-d]嘧啶

公开了在2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)/亚硝酸叔丁酯(TBN)/O2催化下，尿嘧啶/硫尿嘧啶与1,3-二芳基丙烯的高效串联氧化反应。它经历氧化偶联、分子内环化和脱氢芳构化，以中等至优异的产率提供多取代的吡啶并[2,3-d]嘧啶/硫代吡啶并[2,3-d]嘧啶。具有原子经济性高、末端氧化剂绿色、无金属条件等优点。