Electrophilic ipso-Iodocyclization of N-(4-Methylphenyl)propiolamides: Selective Synthesis of 8-Methyleneazaspiro[4,5]trienes
摘要:
[GRAPHICS]A novel and selective method for the synthesis of 8-methylenespiro[4,5]trienes via intramolecular electrophilic ipsoiodocyclization of N-(4-methylphenyl)propiolamides has been developed. In the presence of ICI or I-2, 8-methylene-1-azaspiro[4,5]trienes were selectively prepared from the electrophilic ipso-iodocyclization of N-(4-methylphenyl)propiolamides in moderate to good yields.
Transformations of N-arylpropiolamides to indoline-2,3-diones and acids via C≡C triple bond oxidative cleavage and C(sp2)–H functionalization
作者:Ming-Bo Zhou、Yang Li、Xuan-Hui Ouyang、Jin-Heng Li
DOI:10.1007/s11426-019-9633-x
日期:2020.2
A new palladium-catalyzed oxidative conversion of N-arylpropiolamides and H2O to various indoline-2,3-diones and acids through the C≡C triple bond cleavage and C(sp2)–H functionalization is described, which is promoted by a cooperative action of catalytic CuBr2, 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and O2. The method provides a practical tool for transformations of alkynes by means of a C–H
Access to 3‐(2‐Oxoalkyl)‐azaspiro[4.5]trienones
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Acid‐Triggered Oxidative Cascade Reaction through Alkenyl Peroxide Radical Intermediate
作者:Chang‐Sheng Wang、Thierry Roisnel、Pierre H. Dixneuf、Jean‐François Soulé
DOI:10.1002/adsc.201801203
日期:2019.2
Azaspiro[4.5]trienones bearingketone side chains at the 3‐position are prepared from N‐alkyl‐arylpropiolamides and ketones via oxidative 1,2‐difunctionalization of alkynes. The cascade sequence starts with the generation of alkenyl peroxide intermediates, which are obtained by addition of tert‐butyl hydroperoxide to ketones in presence of a catalytic amount of a strong acid. Then, the ketone radical adds to
Palladium-Catalyzed Conjugate Addition to Electron-Deficient Alkynes with Benzenesulfinic Acid Derived from 1,2-Bis(phenylsulfonyl)ethane: Selective Synthesis of (<i>E</i>)-Vinyl Sulfones
作者:Ren-Jie Song、Yu Liu、Yan-Yun Liu、Jin-Heng Li
DOI:10.1021/jo102359n
日期:2011.2.4
A new, selective method for the synthesis of (E)-vinyl sulfones is presence by palladium-catalyzed C−S bond cleavage/conjugate addition. In the presence of Pd(OAc)2 and DMEDA (N1,N2-dimethylethane-1,2-diamine), 1,2-bis(phenylsulfonyl)ethane underwent the C−S bond cleavage, followed by conjugate addition to numerous electron-deficient alkynes afforded the corresponding (E)-vinyl sulfones in moderate
Palladium Nanoparticle-Catalyzed Stereoselective Domino Synthesis of All-Carbon Tetrasubstituted Olefin Containing Oxindoles via Carbopalladation/C–H Activation
作者:Naziya Parveen、Govindasamy Sekar
DOI:10.1021/acs.joc.0c00915
日期:2020.8.21
catalyzed single-step, stereoselective domino synthesis of symmetrically and unsymmetrically all-carbon tetrasubstituted olefin containing oxindoles from readily accessible anilides has been developed. The Pd-BNP catalyst showed a wide range of functional group tolerance that enabled building a library of heteroaromatics. This reusable Pd catalyst reflected its utility in the synthesis of biologically important
A visiblelight‐induced (blue LED) radical cascade has been devised to effect selenylative spirocyclization of N‐aryl alkynamides at room temperature under oxygen atmosphere and without the aid of external photocatalyst. The protocol is operationally simple, scalable, and offers clean synthesis of 3‐selenospiro[4,5]trienones in high yields (up to 92%). A novel spiro‐ring‐opening strategy has also been