Synthesis of Seleno Oxindoles via Iodine-induced Radical Cyclization of N-arylacrylamides with Diorganyl Diselenides

Synthesis ◽  
2022 ◽  
Author(s):  
Hongmei Jiang ◽  
Haicheng Shen ◽  
Cehua Li ◽  
Zheng Jin ◽  
Yanxue Shang ◽  
...  
Keyword(s):  
Radical Cyclization ◽  
Cascade Cyclization ◽  
Diphenyl Disulfide ◽  
Radical Cascade ◽  
Tandem Cyclization

A mild radical cascade cyclization of N-arylacrylamides with diselenides for the preparation of oxindoles via iodine oxidation is disclosed, which provide an eco-friendly process for the construction of C–Se bond. 25 Examples of N-arylacrylamide substrates were investigated with excellent yields. Besides, the tandem cyclization of acrylamide with diphenyl disulfide was also applicable under the same condition.

A radical cyclization cascade of 2-alkynylbenzonitriles with sodium arylsulfinates

2018 ◽  
Vol 16 (42) ◽  
pp. 7959-7963 ◽  
Author(s):  
Bang Zhou ◽  
Wenqi Chen ◽  
Yuzhong Yang ◽  
Yuan Yang ◽  
Guobo Deng ◽  
...  
Keyword(s):  
Radical Cyclization ◽  
Efficient Approach ◽  
Cascade Cyclization ◽  
Radical Cascade

We report an efficient approach to synthesize sulfonated indenones via a radical cascade cyclization of 2-alkynylbenzonitriles with sodium arylsulfinates.

Direct synthesis of 3-acylbenzothiophenes via the radical cyclization of 2-alkynylthioanisoles with α-oxocarboxylic acids

2018 ◽  
Vol 54 (100) ◽  
pp. 14148-14151 ◽  
Author(s):  
Wei Liu ◽  
Yao-Qian Hu ◽  
Xiao-Yi Hong ◽  
Guo-Xing Li ◽  
Xiao-Bo Huang ◽  
...  
Keyword(s):  
Direct Synthesis ◽  
Radical Cyclization ◽  
Cascade Cyclization ◽  
Direct Route ◽  
Simple Chemical ◽  
Radical Cascade ◽  
Oxocarboxylic Acids

A radical cascade cyclization strategy has been developed to provide a direct route to access 3-acylbenzothiophenes from simple chemical feedstocks.

Fe-Catalyzed Conjunctive Cross-Couplings of Unactivated Alkenes with Grignard Reagents

2020 ◽  
Author(s):  
Lei Liu ◽  
Wes Lee ◽  
Cassandra R. Youshaw ◽  
Mingbin Yuan ◽  
Michael B. Geherty ◽  
...  
Keyword(s):  
Functional Groups ◽  
Cross Coupling ◽  
Alkyl Halides ◽  
Grignard Reagents ◽  
Turnover Frequency ◽  
Diverse Range ◽  
Cascade Cyclization ◽  
Radical Cascade

The first iron-catalyzed three-component cross-coupling of unactivated olefins with alkyl halides and Grignard reagents is reported. The reaction operates under fast turnover frequency and tolerates a diverse range of sp2-hybridized nucleophiles, alkyl halides, and unactivated olefins bearing diverse functional groups to yield the desired 1,2-alkylarylated products with high regiocontrol. Further, we demonstrate that this protocol is amenable for the synthesis of new (hetero)carbocycles including tetrahydrofurans and pyrrolidines via a three-component radical cascade cyclization/arylation that forges three new C-C bonds.

Eosin Y photoredox catalyzed net redox neutral reaction for regiospecific annulation to 3-sulfonylindoles via anion oxidation of sodium sulfinate salts

2018 ◽  
Vol 16 (4) ◽  
pp. 536-540 ◽  
Author(s):  
Rajendra S. Rohokale ◽  
Shrikant D. Tambe ◽  
Umesh A. Kshirsagar
Keyword(s):  
Visible Light ◽  
Eosin Y ◽  
Cascade Cyclization ◽  
Neutral Reaction ◽  
Neutral Process ◽  
Radical Cascade

An eosin Y photoredox catalyzed net redox neutral process for 3-sulfonylindoles via the anionic oxidation of sodium sulfinate salts and its radical cascade cyclization with 2-alkynyl-azidoarenes was developed with visible light as a mediator.

scholarly journals Preparation of optically active bicyclodihydrosiloles by a radical cascade reaction

2013 ◽  
Vol 9 ◽  
pp. 1326-1332 ◽  
Author(s):  
Koichiro Miyazaki ◽  
Yu Yamane ◽  
Ryuichiro Yo ◽  
Hidemitsu Uno ◽  
Akio Kamimura
Keyword(s):  
Silicon Atom ◽  
Cascade Reaction ◽  
Radical Cyclization ◽  
Optically Active ◽  
Unsaturated Ester ◽  
Terminal Alkyne ◽  
Silyl Radical ◽  
Vinyl Radical ◽  
Radical Cascade ◽  
Carbonyl Radical

Bicyclodihydrosiloles were readily prepared from optically active enyne compounds by a radical cascade reaction triggered by tris(trimethylsilyl)silane ((Me3Si)3SiH). The reaction was initiated by the addition of a silyl radical to an α,β-unsaturated ester, forming an α-carbonyl radical that underwent radical cyclization to a terminal alkyne unit. The resulting vinyl radical attacked the silicon atom in an SHi manner to give dihydrosilole. The reaction preferentially formed trans isomers of bicyclosiloles with an approximately 7:3 to 9:1 selectivity.

Iron-catalyzed radical cascade cyclization of oxime esters with isocyanides: synthesis of 1-cyanoalkyl isoquinolines and 6-cyanoalkyl phenanthridines

2021 ◽  
Vol 19 (39) ◽  
pp. 8597-8606
Author(s):  
Dengqi Xue ◽  
Rongqi Liu ◽  
Denggao Zhang ◽  
Ning Li ◽  
Yijie Xue ◽  
...  
Keyword(s):  
Cascade Cyclization ◽  
Radical Cascade

An iron-catalyzed radical cascade cyclization of oxime esters with isocyanides for the synthesis of 1-cyanoalkyl isoquinolines and 6-cyanoalkyl phenanthridines has been developed.

Catalytic Radical Cascade Cyclization of Alkene-Tethered Enones to Fused Bicyclic Cyclopropanols

2021 ◽  
Author(s):  
Ying Xie ◽  
Wei Huang ◽  
Song Qin ◽  
Shaomin Fu ◽  
Bo Liu
Keyword(s):  
Hydrogen Atom ◽  
Cascade Reaction ◽  
Hydrogen Atom Transfer ◽  
Atom Transfer ◽  
Trimethyl Borate ◽  
Cascade Cyclization ◽  
Radical Cascade ◽  
Privileged Scaffolds

An unprecedented hydrogen atom transfer-triggered intramolecular cascade reaction between alkene and enone is developed, using Fe(acac)3, PhSiH2(Oi-Pr) and trimethyl borate, to efficiently construct cis-fused bicyclic cyclopropanols, privileged scaffolds often found...

Electrochemical oxidative radical cascade cyclization of olefinic amides and thiophenols towards the synthesis of sulfurated benzoxazines, oxazolines and iminoisobenzofurans

2021 ◽  
Author(s):  
Fangling Lu ◽  
Jie Xu ◽  
Hao Li ◽  
Ke Wang ◽  
Dandan Ouyang ◽  
...  
Keyword(s):  
Cascade Cyclization ◽  
Radical Cascade

Heterocycles containing N and O are important structures in pharmaceuticals, agrochemicals and functional molecules.

Copper-catalyzed radical cascade cyclization of 2-(allyloxy)arylaldehydes towards chroman-4-one derivatives

2021 ◽  
pp. 153605
Author(s):  
Wenbin Guo ◽  
Linlin Gui ◽  
Xin Chen ◽  
Zhijun Dai ◽  
Liping Wang ◽  
...  
Keyword(s):  
Cascade Cyclization ◽  
Radical Cascade

Alkaloid Synthesis: (-)-Aurantioclavine (Stoltz), (-)-Esermethole (Nakao/Hiyama/ Ogoshi), (-)-Kainic Acid (Tomooka), Dasycarpidone (Bennasar), (-)-Cephalotaxine (Ishibashi) and Lysergic Acid (Fujii/Ohno)

2011 ◽  
Author(s):  
Douglass Taber
Keyword(s):  
Kainic Acid ◽  
Absolute Configuration ◽  
Lysergic Acid ◽  
Ni Catalyst ◽  
Cascade Cyclization ◽  
Alkaloid Synthesis ◽  
Radical Cascade ◽  
The Absolute ◽  
The University ◽  
Stereogenic Center

Intriguing strategies have been developed for the stereocontrolled assembly of complex alkaloid structures. Brian M. Stoltz of Caltech prepared (J. Am. Chem. Soc. 2008, 130, 13745) the enantiomerically-pure alcohol precursor to the secondary amine 1 by enantioselective oxidation of the racemic alcohol. Intramolecular Mitsunobu coupling of 1 then led to (-)-Aurantioclavine 3. Yoshiaki Nakao and Tamejiro Hiyama of Kyoto University and Sensuke Ogoshi of Osaka University developed (J. Am. Chem. Soc. 2008, 130, 12874) an enantioselective Ni catalyst for the cyclization of 4 to 5. Oxidation and cyclization then delivered (-)-Esermethole 6. Although the sulfonamide 7 appears to be prochiral, in fact its two most stable conformations are bent, and enantiomers of each other, with a significant barrier for interconversion. Katsuhiko Tomooka of Kyushu University separated (Tetrahedron Lett. 2008, 49, 6327) the enantiomers of 7, then carried the enantiomercially-pure 7 on, by Pd-catalyzed Cope rearrangement, to 8 and so to (-)-Kainic Acid 9. M.-Lluïsa Bennasar of the University of Barcelona prepared (J. Org. Chem. 2008, 73, 9033) the acyl selenide 11 from the indole 10. While the radical derived from 11 might have been expected to undergo 5-exo cyclization, in the event the 6-endo mode dominated, to give Dasycarpidone 12 and its diastereomer. Hiroyuki Ishibashi of Kanazawa University showed (Organic Lett. 2008, 10, 4129) that the radical cascade cyclization of the enamine 13, derived from diethyl tartrate, proceeded with remarkable diastereocontrol, to give 14. The amide 14 was converted to (-)-Cephalotaxine 15. Nobutaka Fujii and Hiroaki Ohno, also of Kyoto University, used (Organic Lett. 2008, 10, 5239) a Pd catalyst to mediate the cascade cyclization of 16 to 17. Although 16 has two stereogenic centers, including the allene, it is the aminated stereogenic center of 17 that sets the absolute configuration of the product Lysergic Acid 18. One intermediate in the conversion of 16 to the tetracyclic 17 is the tricyclic π-allyl Pd complex. If all the material could be channeled through that pathway, there is a good chance that the chiral Trost catalyst could effectively control the absolute configuration of the aminated stereogenic center as it is formed, leading to the enantiomerically enriched product 18.

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