A series of optically active pyrano[3,2-c]chromenes have been synthesized through an asymmetric domino reaction of 4-hydroxy-2H-chromen-2-ones with malononitriles. The targeted molecules were obtained in excellent yields and enantioselectivities (up to 94% yield, 99% ee). The AChE inhibitory activity studies revealed that compounds 4n (IC50 = 21.3 μM) and 4p (IC50 = 19.2 μM) displayed potent acetylcholinesterase
通过4-羟基-2 H-苯甲基-2-酮与丙二腈的不对称多米诺反应,合成了一系列旋光的吡喃并[3,2- c ]色烯。以优异的收率和对映选择性(高达94%的收率,99%ee)获得了目标分子。AChE抑制活性研究表明,化合物4n(IC 50 = 21.3μM)和4p(IC 50 = 19.2μM)显示出有效的乙酰胆碱酯酶抑制作用。在大多数情况下,S-对映异构体优于相应的R-对映体。此外,分子建模为理解这类化合物对AChE的对映选择性提供了一种实用的方法。
Sulfinate‐Organocatalyzed (3+2) Annulation of Allenyl Sulfones with 1,1‐Dicyano Olefins in the Presence of a Quaternary Ammonium Phase Transfer Agent
benzenesulfinate‐catalyzed (3+2) annulation between allenylsulfones and aryl(alkyl)idenemalononitriles has been developed under mild phasetransfer conditions, affording a breadth of functionalized sulfonyl cyclopentenes in good to excellent yields (22 examples, 49–99%) and high diastereoselectivities. These adducts were likely generated, via an allylsulfone anion featuring a quaternaryammonium cation.
Carbene-Catalyzed Reaction of Indolyl Methylenemalononitriles and Enals for Access to Complex Tetrahydrocarbazoles
作者:Chengli Mou、Liejin Zhou、Runjiang Song、Huifang Chai、Lin Hao、Yonggui Robin Chi
DOI:10.1021/acs.orglett.0c00418
日期:2020.4.3
A carbene-catalyzed enantioselectivecascadereaction of substituted methylenemalononitriles and α-bromoenals is disclosed. Key steps of this cascade process include a formal [4 + 2] cycloaddition, aldolreaction, and intramolecular lactonization. Our reaction offers streamlined and highly stereoselective access to complex tetrahydrocarbazole derivatives, with simultaneous formation of four chemical
Sparteine Thiourea: The Synthesis of an N Chiral Bispidine-Quinolizidine-Derived Organocatalyst and Applications in Asymmetric Synthesis of Dihydropyrano[c]chromenes
作者:Hexin Sun、Lin Huang、Jianhui Huang
DOI:10.1021/acs.joc.4c00638
日期:2024.5.17
ligands in asymmetricsynthesis. In particular, a chiral bispidine-quinolizidine hybrid, such as sparteine, was utilized in asymmetricsynthesisinvolving a metal, exhibiting superior catalytic activity. In this study, we report the design and synthesis of a series of sparteine-derived organocatalysts and the utilization of these catalysts in tandem Michael addition–cyclization reactions. These catalysts
Bispidine 是一种桥联双环二胺,已广泛用作不对称合成中手性螯合配体的刚性支架。特别是,手性双吡啶-喹啉西啶杂化物(例如金雀花碱)被用于涉及金属的不对称合成中,表现出优异的催化活性。在这项研究中,我们报告了一系列金雀花衍生的有机催化剂的设计和合成,以及这些催化剂在串联迈克尔加成环化反应中的应用。这些催化剂表现出优异的催化反应活性和对映选择性,并且以较低的催化剂负载量制备了相应的二氢吡喃并[ c ]色烯,收率≤99%,ee≤99%。回收的催化剂即使在经过四次循环后仍保持良好的催化性能,并且还进行了1%催化剂负载量的克级反应,提供了96%的收率和98%ee的产物。