Enantioselective Organocatalytic Domino Michael/Aldol Reactions: An Efficient Procedure for the Stereocontrolled Construction of 2<i>H</i>-Thiopyrano[2,3-b]quinoline Scaffolds
An efficientprocedure for the stereocontrolledconstruction of 2H‐thiopyrano[2,3‐b]quinolinescaffolds has been developed, starting from simple compounds. The dominoMichael/aldolreactions between 2‐mercaptobenzaldehydes and enals, promoted by chiral diphenylprolinol TMS ether, proceed with excellent chemo‐ and enantioselectivity to give the corresponding synthetically useful and pharmaceutically
从简单的化合物开始,已经开发出了一种有效的立体控制2 H -thiopyrano [2,3-b]喹啉骨架的方法。手性二苯基脯氨醇TMS醚促进的2-巯基苯甲醛与烯醛之间的多米诺米歇尔/羟醛反应,具有出色的化学和对映选择性,可提供相应的合成上有用的和药学上有价值的2 H-硫代吡喃并[2,3-b]喹啉ee的产率为90–99%。
Rapid, clean and efficient one-pot synthesis of thiopyrano[2,3-b]quinolines via domino Michael addition/cyclization reactions
作者:Bhawana Singh、Atish Chandra、Mrityunjaya Asthana、Radhey M. Singh
DOI:10.1016/j.tetlet.2012.04.032
日期:2012.6
Rapid and efficient one-pot synthesis of thiopyrano[2,3-b]quinolines is described from the reaction of 3-formyl-quinoline-2-thiones with acrylonitrile using economical organic base Et3N at room temperature. The reaction proceeded smoothly via domino Michaeladdition/cyclization reactions and did not require dry solvent, inert atmosphere and column chromatography purifications.
从3-甲酰基-喹啉-2-硫酮与丙烯腈在室温下使用经济的有机碱Et 3 N反应,可以快速高效地一锅合成噻吩并[2,3- b ]喹啉。该反应通过多米诺骨牌迈克尔加成/环化反应顺利进行,不需要干燥溶剂,惰性气氛和柱色谱法纯化。
Synthesis of Optically Active 2<i>H</i>-Thiopyrano[2,3-<i>b</i>]quinolines with Three Contiguous Stereocenters<i>via</i>an Organocatalytic Asymmetric Tandem Michael-Henry Reaction
Optically active 2H‐thiopyrano[2,3‐b]quinolines with threecontiguousstereocenters have been synthesized via a chiral bifunctional squaramide‐catalyzed tandem Michael–Henry reaction between 2‐mercaptoquinoline‐3‐carbaldehydes and nitroolefins. The reactions proceed with excellent diastereo‐ and enantioselectivity to give the title compounds in high yields with high levels of diastereo‐ and enantioselectivity
光学活性的2 H-硫代吡喃并[2,3- b ]喹啉具有三个连续的立体中心,是通过2-巯基喹啉-3-甲醛与硝基烯烃之间的手性双官能方酰胺催化的迈克尔-亨利串联反应合成的。反应以极好的非对映和对映选择性进行,以高收率得到标题化合物,同时具有高水平的非对映和对映选择性(分别高达> 99/1 dr和> 99%ee)。
Organocatalyzed Highly Diastereo- and Enantioselective Tandem Sulfa-Michael-Mannich Reaction of 2-Mercaptoquinoline-3-carbaldimines with Maleimides
A highly diastereo‐ and enantioselectiveorganocatalyzed domino sulfa‐Michael–Mannich reaction of 2‐mercaptoquinoline‐3‐carbaldimines with maleimides has been developed. This approach provides a convenient and efficient access to multifuntionalized tetracyclic quinoline derivatives with three contiguous stereocenters in high yield with excellent stereoselectivity (up to >99:1 dr and >99 % ee).