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1.
The first enantioselective cyanoamidation of olefins provides quick access to a variety of 3,3-disubstituted oxindoles. The combination of Pd(dba)2, an optically active phosphoramidite, and N, N-dimethylpropylene urea (DMPU) in decalin were found to be the best conditions. 相似文献
2.
Synthesis of 3,3-disubstituted oxindoles 总被引:1,自引:0,他引:1
A novel and efficient two-step synthetic sequence for the preparation of 3,3-disubstituted oxindoles was developed starting from arylhydrazines and α-branched aldehydes via Fischer indole type synthesis followed by imine oxidation. 相似文献
3.
This study examines a domino carbopalladation-cross-coupling reaction for the formation of valuable oxindole scaffolds. Furthermore, the reaction sequence forges vicinal stereocenters in a stereospecific manner through the formation of two carbon-carbon bonds and, thereby, rapidly generates complexity. The reaction gives high yields for a variety of acrylamide substrates, and various organoboranes have also been evaluated for the cross-coupling. This work offers insight into the relative rates determining a successful carbopalladation-cross-coupling reaction and how to favor the desired reaction pathway. 相似文献
4.
Atsuo Nakazaki Ayako Mori Susumu Kobayashi Toshio Nishikawa 《Tetrahedron letters》2012,53(52):7131-7134
Diastereoselective synthesis of 3,3-disubstituted oxindoles has been examined by transformations involving nucleophilic addition, alkylation, and cycloaddition using chiral racemic N-aryl oxindoles bearing C–N axial chirality. The most striking features of this approach are high diastereoselectivities (up to >95:<5) when using ortho-monosubstituted N-aryl oxindoles and easy removal of the p-(benzyloxy)aryl moiety in the axially twisted amides by a mild two-step sequence. 相似文献
5.
The catalytic asymmetric synthesis of 3,3-disubstituted oxindoles, a big family of privileged scaffolds in natural products and drugs, is of current interest. Recently, the catalytic asymmetric functionalization of diazooxindoles emerges as a potentially general and flexible strategy for this purpose, with several notable examples coming out in 2013. In this digest, synthetic applications of diazooxindoles have been summarized and discussed, which might be helpful for readers to understand the special properties of this type of donor/acceptor cyclic diazo reagent and to develop new catalytic asymmetric reactions. 相似文献
6.
The alkylation of 1-thiophthalides followed by treatment of the reaction mixture with triethylamine constitutes a convenient method of preparing 3,3-disubstituted 2-thiophthalides.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 172–174, February, 1991. 相似文献
7.
Shyam Krishnan 《Tetrahedron letters》2007,48(43):7571-7573
A method for the synthesis of 3,3-disubstituted oxindole derivatives is described. This involves the base-mediated addition of malonate esters to 3-halo-3-alkyloxindoles. The addition is tolerant of a range of alkyl substituents at position 3 of the oxindole. Addition to an aryl chloro-oxindole is also described. 相似文献
8.
Zhao-Zhao Zhou Hui-Liang Hua Jian-Yi Luo Zi-Sheng Chen Ping-Xin Zhou Xue-Yuan Liu Yong-Min Liang 《Tetrahedron》2013
Metal-free synthesis of 3,3-disubstituted oxindoles utilizing N-arylacrylamides and simple alcohols is developed. It provides an efficient method for preparing a series of hydroxyl-containing oxindole derivatives. This reaction is proposed to proceed through oxidative radical cyclization mechanism. The remarkable features of the reaction are metal-free condition and excellent functional group tolerance. 相似文献
9.
The synthesis of two different sets of 3,3-disubstituted oxetane building blocks is described. These molecules can be usefully incorporated in more complex structures to modulate their metabolic and physicochemical properties. The synthetic pathways are general and could be exploited for the synthesis of many other related derivatives. 相似文献
10.
Mohit L. Deb 《合成通讯》2013,43(12):2240-2243
The reaction of isatin and indoles in refluxing water/ethanol (7:3) affords 3,3′-di(indolyl)oxindoles in excellent yields. 相似文献
11.
Zhen-Hua Xing Ying Zhang Yong Wang Xiao-Ping Xu Shun-Jun Ji 《Tetrahedron letters》2017,58(12):1094-1097
An organocatalytic asymmetric functionalization of C(3)S bond of indolone by naphthol is described. It provided a new and simple method for the construction of 3,3-disubstituted indolones containing a fresh-formed chiral quaternary carbon center with high yield and good enantioselectivity. 相似文献
12.
Ce Shi 《Tetrahedron》2007,63(35):8563-8570
Asymmetric synthesis of 6,7-dimethoxy-1-vinyltetrahydroisoquinolines through Pd-catalyzed intramolecular allylic amination of 3-(amidoethylphenyl)prop-2-enyl carbonates was studied, using a library of fine-tunable monodentate phosphoramidite ligands. Under optimized conditions, excellent enantiopurity (up to 96% ee) and 100% product selectivity were achieved. 1-Vinyltetrahydroquinoline thus obtained is a highly versatile intermediate for the synthesis of various biologically active alkaloids of medicinal interest. 相似文献
13.
Nandarapu Kumarswamyreddy Kanduru Lokesh Venkitasamy Kesavan 《Tetrahedron letters》2018,59(49):4344-4348
3-Alkynyl-3-OBoc oxindoles underwent Cu(II) mediated Friedel-Crafts alkylation with indoles and phenols to yield of structurally diverse 3-alkynyl-3-indole/phenol-oxindole derivatives. The synthetic application of alkylated phenol derivatives were further demonstrated to biologically important new class of chromene fused spirooxindoles through intramolecular metal-free iodocyclization under mild reaction conditions with broad substrate scope in very good yields. 相似文献
14.
[reaction: see text] The five- to seven-membered alpha-alkylidene lactams were prepared in 45-99% yield by the palladium-catalyzed cyanoamidation of alkynyl cyanoformamides. The reaction proceeded exclusively in a 5-exo mode, giving the corresponding (Z)-alkenes as major products. The reaction was also applied to 1,1-disubstituted alkenes to afford oxindoles bearing a quaternary carbon center. 相似文献
15.
A new efficient synthesis of aromatic six-membered ring sultones by the implementation of ligand-free Pd-catalyzed intramolecular cyclization of aromatic sulfonates derived from various bromo phenols and naphthols is described. 相似文献
16.
Two types of quinoline scaffolds were constructed in a combinatorial format via the Ugi four-component reaction (U-4CR) and Pd-catalyzed intramolecular arylation reaction. The scope of this two-step synthetic sequence was examined from commercially available and synthetically accessible starting materials. 相似文献
17.
18.
Synthesis of hitherto unreported benzodiazocine-annulated heterocycles by the implementation of palladium-catalyzed intramolecular Heck reaction has been achieved in excellent yields. 相似文献
19.
A new strategy for the synthesis of condensed hetero- or carbocycles such as pyrroloindoles or fluorenes has been developed that involves the Pd-catalyzed cyclization of readily available N-(2-halobenzyl)pyrroles or their phenyl derivatives. The reaction is proposed to proceed via oxidative addition of benzylic halides to Pd(0) followed by base-assisted C-H bond activation. A broad range of condensed cyclic products could be obtained in good to excellent yields under mild conditions. 相似文献