Organocatalytic enantioselective conjugate addition of ketones to isatylidine malononitriles
作者:Lu Liu、Deyan Wu、Xiangmin Li、Sinan Wang、Hao Li、Jian Li、Wei Wang
DOI:10.1039/c2cc17067a
日期:——
An enantioselective Michael addition of ketones to alkylidenemalononitriles catalyzed by chiral primary amine I with (R)-5c as a co-catalyst in good yields (>90%) and with good enantioselectivities (85–96% ee) has been developed. The strategy has also been extended to a three-component version through a domino Knoevenagel/Michael sequence with similar or better outcomes.
Enantioselective Construction of Spiro[2H-pyran-3,4′-indoline] by a Systematic Michael/Reduction/Cyclization Sequence Triggered by the Asymmetric Conjugate Addition of Ketones to Isatylidenemalononitriles
作者:Hua Zhao、Yu-Bao Lan、Zhao-Min Liu、Yong Wang、Xing-Wang Wang、Jing-Chao Tao
DOI:10.1002/ejoc.201101810
日期:2012.4
derivatives by a systematic Michael/reduction/cyclization sequence. The initial Michael addition of isatylidenemalononitriles with ketones was catalyzed by a cinchona-based chiral primaryamine and L-camphorsulfonic acid and furnished multifunctional, optically active Michael adducts in high yields (81–99 %) with excellent enantioselectivities (95 to >99 % ee). Subsequently, the Michael adducts were converted
3位带有多取代杂环基序和四元立体中心的杂环螺茚吲哚广泛存在于大量螺茚吲哚生物碱中,是具有显着生物活性的药学相关化合物。在本文中,我们报告了一种通过系统的迈克尔/还原/环化序列构建对映体富集的螺[2H-吡喃-3,4'-二氢吲哚]衍生物的有效方法。异亚烷基丙二腈与酮的初始迈克尔加成由基于金鸡纳的手性伯胺和 L-樟脑磺酸催化,并以高产率 (81–99%) 提供多功能、旋光迈克尔加合物,并具有出色的对映选择性 (95% 至 >99% ee )。随后,迈克尔加合物转化为螺[2H-吡喃-3,
<scp>l</scp>-Proline-Grafted Mesoporous Silica with Alternating Hydrophobic and Hydrophilic Blocks to Promote Direct Asymmetric Aldol and Knoevenagel–Michael Cascade Reactions
作者:Zhe An、Ying Guo、Liwei Zhao、Zhi Li、Jing He
DOI:10.1021/cs500385s
日期:2014.8.1
enantioselectivity in the directaldolreaction and the Knoevenagel–Michael cascade reaction. The l-proline loading could be reduced to as low as 0.63 mol %, giving 95% ee for anti-isomers and 81% ee for syn-isomers in the catalytic asymmetricaldolreaction of nitrobenzaldehyde and cyclohexanone, which was hard to accomplish on the homogeneous counterpart. In the directasymmetricaldolreaction of ethyl-2-oxoacetate
Primary-tertiary diamine-catalyzed Michael addition of ketones to isatylidenemalononitrile derivatives
作者:Akshay Kumar、Swapandeep Singh Chimni
DOI:10.3762/bjoc.10.91
日期:——
Simple primary-tertiary diamines easily derived from natural primary aminoacids were used to catalyze the Michael addition of ketones with isatylidenemalononitrile derivatives. Diamine 1a in combination with D-CSA as an additive provided Michael adducts in high yield (up to 94%) and excellent enantioselectivity (up to 99%). The catalyst 1a was successfully used to catalyze the three-component version