A one-pot cascade heterocyclization strategy has been developed for the synthesis of 2,4-dichloro-substituted pyrano[2,3-d]pyrimidines and furo[2,3-d]pyrimidines from linear γ- and β-ketomalononitriles using triphosgene and triphenylphosphine oxide. The reaction afforded synthetic useful products with moderate to good yields, bypassing the conventional harsh conditions of chlorination. The mechanistic
已开发出一锅级联杂环化策略,使用
三光气从线性γ-和β-酮基
乙腈合成2,4-二
氯取代的
吡喃并[2,3- d ]
嘧啶和
呋喃并[2,3- d ]
嘧啶和
三苯基氧化膦。该反应绕开了常规的苛刻
氯化条件,提供了具有中等至良好收率的合成有用产物。机理研究表明反应是通过非
异氰酸酯途径进行的,第二步可能以三苯膦氧化物催化的方式进行。