strategy for the regioselective assembly of 2-aminoimidazole derivatives is herein described. Through a transition metal-free domino addition/cyclization process, the reactions of unsymmetrical carbodiimides with propargylic amines mediated by Cs2CO3 selectively afforded the corresponding polysubstituted 2-aminoimidazoles in moderate to good yields under very mild conditions. The regioselectivity was reversed
本文描述了2-氨基咪唑衍生物的区域选择性组装的方便的单步策略。通过无过渡金属的多米诺加成/环化过程,不对称碳二亚胺与Cs 2 CO 3介导的炔丙基胺的反应在非常温和的条件下以中等至良好的收率选择性地提供了相应的多取代的2-氨基咪唑。在较高温度下,在TEA存在下,区域选择性反转。所获得的2-(邻碘芳基)氨基咪唑可以容易地转化为2-(2-联苯基)氨基咪唑,2-(邻炔基苯基)氨基咪唑,苯并咪唑并[1,2- a ]咪唑和N-(咪唑-2-基)吲哚衍生物。
A concise synthesis of 4-imino-3,4-dihydroquinazolin-2-ylphosphonates via a palladium-catalyzed reaction of carbodiimide, isocyanide, and phosphite
作者:Guanyinsheng Qiu、Yuan Lu、Jie Wu
DOI:10.1039/c2ob26979a
日期:——
A palladium-catalyzedreaction of 2-iodoarylcarbodiimide, isocyanide, and phosphite leads to 4-imino-3,4-dihydroquinazolin-2-ylphosphonates in moderate to good yields. Three bonds are formed in a one pot procedure and the tandem process includes nucleophilic attack, isocyanide insertion, and C–N coupling.
Copper-Catalyzed Cascade Addition/Cyclization: An Efficient and Versatile Synthesis of <i>N</i>-Substituted 2-Heterobenzimidazoles
作者:Xin Lv、Weiliang Bao
DOI:10.1021/jo900743y
日期:2009.8.7
A novel and efficient one-pot synthesis of various N-substituted 2-heterobenzimidazoles has been developed. Through a Cu(I)-catalyzed cascade intermolecular addition/intramolecular C−Ncouplingprocess, a wide variety of 2-heterobenzimidazoles could be synthesized from o-haloarylcarbodiimides and N- or O-nucleophiles.
assembly of 2-substituted benzimidazoles and 2-benzimidazolones has been developed. Under very mild copper catalysis or transition metal-free conditions, a wide range of the 2-alkyl/alkenyl benzimidazole derivatives can be conveniently and selectively synthesized through the domino reactions of o-haloarylcarbodiimides with active methylene species. Interesting complimentary effect was discovered under the
copper(I)‐catalysed domino transformation for the synthesis of tricyclic imidazobenzimidazole derivatives was developed. Using readily available primary propargylic amines and o‐haloarylcarbodiimides as the starting materials, a variety of substituted benzo[d]imidazo[1,2‐a]imidazoles was efficiently and selectively assembled. Further investigations indicated that the dominoreaction was likely the result
开发了铜(I)催化的多米诺变换,用于合成三环咪唑并苯并咪唑衍生物。使用现成的伯炔丙基胺和邻卤代芳基碳二亚胺作为起始原料,可以有效地,选择性地组装各种取代的苯并[ d ]咪唑并[1,2- a ]咪唑。进一步的研究表明,多米诺骨牌反应可能是新颖的加成/环异构化/偶联过程的结果。