3-Pyrrolyl-oxindoles as efficient nucleophiles for organocatalytic asymmetric synthesis of structurally diverse 3,3′-disubstituted oxindole derivatives
Organocatalytic Asymmetric Michael/Friedel–Crafts Cascade Reaction of 3-Pyrrolyl-oxindoles and α<i>,</i>β-Unsaturated Aldehydes for the Construction of Chiral Spiro[5,6-dihydropyrido[1,2-<i>a</i>]pyrrole-3,3′-oxindoles]
An efficient and unprecedented organocatalyticasymmetricreaction of 3-pyrrolyl-oxindoles with α,β-unsaturated aldehydes to generate spirocyclic oxindole compounds was developed. The reactions were catalyzed by diphenylprolinol silyl ether and 2-fluorobenzoic acid via an asymmetricMichael/Friedel–Crafts cascade process, followed by dehydration with p-toluenesulfonic acid to afford a wide variety
研究了3-吡咯基-羟基吲哚与α,β-不饱和醛的高效有机催化不对称反应,以生成螺环型羟吲哚化合物。该反应是由二苯基脯氨醇甲硅烷基醚和2-氟苯甲酸通过不对称的Michael / Friedel-Crafts级联过程催化的,然后用对甲苯磺酸进行脱水,从而得到各种结构多样的螺[5,6-二氢吡啶基[1, 2- a ]吡咯-3,3'-oxindole]衍生物,收率高(高达93%),非对映选择性和对映选择性高(至> 99:1 dr和97%ee)。
Bifunctional tertiary amine-squaramide catalyzed asymmetric catalytic 1,6-conjugate addition/aromatization of para-quinone methides with oxindoles
作者:Yu-Hua Deng、Xiang-Zhi Zhang、Ke-Yin Yu、Xu Yan、Ji-Yuan Du、Hanmin Huang、Chun-An Fan
DOI:10.1039/c5cc10502a
日期:——
Asymmetric catalytic 1,6-addition of p-QMs with racemic oxindoles under the bifunctionalcatalysis of C2-symmetric dimeric Cinchona-derived squaramides is described. This tertiary amine-squaramide catalzyed reaction provides a diastereoselective and enantioselective approach...
Organocatalytic Asymmetric Synthesis of Aza-Spirooxindoles via Michael/Friedel–Crafts Cascade Reaction of 1,3-Nitroenynes and 3-Pyrrolyloxindoles
作者:Qijian Ni、Xuyang Wang、Da Zeng、Qianling Wu、Xiaoxiao Song
DOI:10.1021/acs.orglett.1c00409
日期:2021.3.19
An asymmetric [3+3] cyclization of nitroenynes and 3-pyrrolyloxindoles has been realized with a chiral bifunctional squaramide catalyst. This Michael/Friedel–Crafts cascade strategy provides a facile and efficient access to enantioenriched polycyclic aza-spirooxindoles with 32–95% isolated yields and excellent stereocontrol under mild reaction conditions.
Enantioselective Synthesis of 3,3-Disubstituted Oxindoles Bearing Two Different Heteroatoms at the C3 Position by Organocatalyzed Sulfenylation and Selenenylation of 3-Pyrrolyl-oxindoles
Catalytic asymmetric sulfenylation and selenenylation of 3-pyrrolyl-oxindoles for the synthesis of 3,3-disubstituted oxindoles bearing two different heteroatoms at the C3 position have been achieved with commercially available cinchonidine as catalyst. A wide range of optically active 3-thio-3-pyrrolyl-oxindoles and 3-seleno-3-pyrrolyl-oxindoles could be smoothly obtained under mild conditions with
Sequential Nucleophilic <i>C</i>
(sp<sup>3</sup>
)-Benzylation/C(sp<sup>2</sup>
)-H Arylation for the Synthesis of Spiro[oxindole-3,5′-pyrrolo[2,1-<i>a</i>
]isoquinolines]
using sequential nucleophilic C(sp3)-benzylation and palladium-catalyzedC(sp2)–H arylation reactions of 3-pyrrolyloxindoles and 2-(bromomethyl)aryl bromides, a series of spiro[oxindole-3,5′-pyrrolo[2,1-a]isoquinolines] were smoothly obtained in up to 92 % yield. A synthetic application of this method was also demonstrated by the transformation of 3u into functionalized compound 4. Moreover, the catalytic