Enantioselective Metal-Free Hydrogenations of Disubstituted Quinolines
作者:Zhenhua Zhang、Haifeng Du
DOI:10.1021/acs.orglett.5b03307
日期:2015.12.18
A metal-freehydrogenation of 2,4-disubstituted quinolines was realized for the first time using chiral diene derived borane catalysts to furnish the corresponding tetrahydroquinolines in 75–98% yields with 95/5−99/1 dr’s and 86–98% ee’s. This catalytic system was also effective for 2,3-disubstituted quinolines to give moderate to good ee’s.
A series of substituted quinolines was prepared from arylamines, aldehydes, and terminal olefins (see scheme). The palladium‐catalyzed sequentialformation of CCbonds proceeds smoothly with both electron‐deficient and electron‐rich olefins. When acrylic acid is used as terminal olefin, decarboxylation occurs to provide 2‐substituted quinolines.
Acid-promoted iron-catalysed dehydrogenative [4 + 2] cycloaddition for the synthesis of quinolines under air
作者:Jinfei Yang、Xiao Meng、Kai Lu、Zhihao Lu、Minliang Huang、Chengniu Wang、Fei Sun
DOI:10.1039/c8ra06826g
日期:——
An acid-promoted iron-catalysed dehydrogenative [4 + 2] cycloaddition reaction was developed for the synthesis of quinolines using air as a terminal oxidant. Acetic acid was the best cocatalyst for the cycloaddition of N-alkyl anilines with alkenes or alkynes under air. Various quinoline derivatives were obtained in satisfactory-to-excellent yields, and no other byproducts besides water were produced
开发了一种酸促进的铁催化脱氢 [4 + 2] 环加成反应,用于以空气为末端氧化剂合成喹啉。乙酸是N-烷基苯胺与烯烃或炔烃在空气中环加成的最佳助催化剂。各种喹啉衍生物均以令人满意至优异的收率得到,且反应中除水外未产生其他副产物。斑马鱼模型已成为评价药物作用的重要脊椎动物模型。我们测试了斑马鱼中3n的活性。试验结果表明,1 μg mL -1 3n处理导致形态畸形,0.01~0.1 μg mL -1 3n治疗导致斑马鱼胚胎中出现严重的血管生成缺陷。该研究成果对推进心脑血管疾病药物研究具有重要意义。
Formal [4+2]-Annulation of Vinyl Azides with N-Unsaturated Aldimines
functionalized quinolines and pyridines could be synthesized by BF3⋅OEt2‐mediated reactions of vinylazides with N‐aryl and N‐alkenyl aldimines, respectively. The reaction mechanism could be characterized as formal [4+2]‐annulation, including unprecedented enamine‐type nucleophilic attack of vinylazides to aldimines and subsequent nucleophilic cyclization onto the resulting iminodiazonium ion moieties.