One-Pot Cascade Heterocyclization of γ- and β-Ketomalononitriles to 2,4-Dichloro-Substituted Pyrano[2,3-<i>d</i>]pyrimidines and Furo[2,3-<i>d</i>]pyrimidines Mediated by Triphosgene and Triphenylphosphine Oxide
作者:Zhen-Hua Li、Zhi-Jiang Jiang、Qiao-Ling Shao、Jin-Jing Qin、Qiang-Feng Shu、Wen-Hao Lu、Wei-Ke Su
DOI:10.1021/acs.joc.8b00669
日期:2018.6.15
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。