38002-48-1Relevant academic research and scientific papers
Selective Rhodium-Catalyzed Hydroformylation of Terminal Arylalkynes and Conjugated Enynes to (Poly)enals Enabled by a π-Acceptor Biphosphoramidite Ligand
Zhao, Jiangui,Zheng, Xueli,Tao, Shaokun,Zhu, Yuxin,Yi, Jiwei,Tang, Songbai,Li, Ruixiang,Chen, Hua,Fu, Haiyan,Yuan, Maolin
, p. 6067 - 6072 (2021/08/16)
The hydroformylation of terminal arylalkynes and enynes offers a straightforward synthetic route to the valuable (poly)enals. However, the hydroformylation of terminal alkynes has remained a long-standing challenge. Herein, an efficient and selective Rh-catalyzed hydroformylation of terminal arylalkynes and conjugated enynes has been achieved by using a new stable biphosphoramidite ligand with strong π-acceptor capacity, which affords various important E-(poly)enals in good yields with excellent chemo- and regioselectivity at low temperatures and low syngas pressures.
Aminium cation-radical catalysed selective hydration of (E)-aryl enynes
Giel, Marie-Claire,Barrow, Andrew S.,Smedley, Christopher J.,Lewis, William,Moses, John E.
supporting information, p. 6991 - 6994 (2021/07/21)
The hydration of carbon-carbon triple bonds is an important and atom economic synthetic transformation. Herein, we report a mild and selective method for the catalytic Markovnikov hydration of (E)-aryl enynes to the corresponding enones, mediated through the bench-stable aminium salt, tris(4-bromophenyl)ammoniumyl hexachloroantimonate (TBPA). The chemoselective and diastereoselective method proceeds under neutral metal-free conditions, delivering excellent product yields from terminal and internal alkyne units. The synthesis of biologically important (E)-3-styrylisocoumarins, including a formal synthesis of the natural product achlisocoumarin III, demonstrates the utility of this novel transformation.
Triazole-curcuminoids: A new class of derivatives for 'tuning' curcumin bioactivities?
Caprioglio, Diego,Torretta, Simone,Ferrari, Maila,Travelli, Cristina,Grolla, Ambra A.,Condorelli, Fabrizio,Genazzani, Armando A.,Minassi, Alberto
, p. 140 - 152 (2015/12/31)
Curcumin is a unique blend of pharmacophores responsible for the pleiotropy of this natural pigment. In the present study we have replaced the 1,3-dicarbonyl moiety with a 1,2,3-triazole ring to furnish a new class of triazole-curcuminoids as a possible strategy to generate new compounds with different potency and selectivity compared to curcumin. We obtained a proof-of-principle library of 28 compounds tested for their cytotoxicity (SY-SY5Y and HeLa cells) and for their ability to inhibit NF-κB. Furthermore, we also generated 1,3-dicarbonyl curcuminoids of selected click compounds. Triazole-curcuminoids lost their ability to be Michael's acceptors, yet maintained some of the features of the parent compounds and disclosed new ones. In particular, we found that some compounds were able to inhibit NF-κB without showing cytotoxicity, while others, unlike curcumin, activated NF-κB signalling. This validates the hypothesis that click libraries can be used to investigate the biological activities of curcumin as well as generate analogs with selected features.
Z-Selective (Cross-)Dimerization of Terminal Alkynes Catalyzed by an Iron Complex
Rivada-Wheelaghan, Orestes,Chakraborty, Subrata,Shimon, Linda J. W.,Ben-David, Yehoshoa,Milstein, David
supporting information, p. 6942 - 6945 (2016/06/13)
Efficient iron-catalyzed homocoupling of terminal alkynes and cross-dimerization of aryl acetylenes with trimethylsilylacetylene is reported. The complex [Fe(H)(BH4)(iPr-PNP)] (1) catalyzed the (cross-)dimerization of alkynes at room temperatur
Intermolecular [3+2] Annulation of Cyclopropylanilines with Alkynes, Enynes, and Diynes via Visible Light Photocatalysis
Nguyen, Theresa H.,Morris, Scott A.,Zheng, Nan
supporting information, p. 2831 - 2837 (2016/02/18)
One-step syntheses of carbocycles substituted with amines from simple starting materials remain rare. We recently developed an intermolecular [3+2] annulation of cyclopropylanilines with alkenes and alkynes that enables this one-step synthesis. Herein, we
Expeditious cascade reactions: Controlled syntheses of fenestradienes and cyclooctatrienes under palladium catalysis
Charpenay, Mélanie,Boudhar, Aicha,Hulot, Catherine,Blond, Ga?lle,Suffert, Jean
, p. 7568 - 7591 (2013/08/23)
Palladium cyclization cascades represent an elegant way to access complex polycyclic scaffolds in a minimum amount of steps. Herein we provide a complete account on two new methodologies including these kind of cascades, each leading to two types of attractive compounds, cyclooctatrienes and [4.6.4.6] fenestradienes. The reader will first discover a strategy requiring three steps starting from alkenyl bromides, based on a first 4-exo-dig carbopalladation/ Sonogashira coupling tandem reaction, and a subsequent P-2 Ni induced semi-hydrogenation. This leads to a first generation of cyclooctatrienes and [4.6.4.6]fenestradienes. Next, the second approach will be presented, in which the second generation of these compounds is accessed in a one-pot reaction including five steps, starting from the same alkenyl bromide compounds. These methods are appealing in terms of atom economy, the use of easy to handle conditions as well as the variability of its scope.
Conjugated enyne synthesis by rearrangement of acetylenic epoxides mediated by low-valence organotitanium and organozirconium reagents
Denichoux, Aurélien,Cyklinsky, Mathieu,Chemla, Fabrice,Ferreira, Franck,Pérez-Luna, Alejandro
, p. 1001 - 1005 (2013/06/27)
The rearrangement of acetylenic epoxides mediated by low-valence organotitanium and organozirconium reagents is -reported to give conjugated enynes. Moderate to good yields and high selectivities are obtained when using the organozirconium(II) Negishi rea
Copper-catalyzed highly selective semihydrogenation of non-polar carbon-carbon multiple bonds using a silane and an alcohol
Semba, Kazuhiko,Fujihara, Tetsuaki,Xu, Tinghua,Terao, Jun,Tsuji, Yasushi
supporting information; experimental part, p. 1542 - 1550 (2012/08/08)
A copper catalyst bearing a suitable Xantphos derivative or NHC ligand was found to be highly efficient for the selective semihydrogenation of non-polar unsaturated compounds using a mixture of a silane and an alcohol as reducing agent. The catalytic system was useful for the selective semihydrogenation of internal alkynes to (Z)-alkenes with suppression of overreduction to the corresponding alkanes. Furthermore, semihydrogenations of terminal alkyne, 1,2-diene, 1,3-diene, 1,3-enyne and 1,3-diyne systems were also achieved selectively. Copyright
Sonogashira cross-coupling reactions and construction of the indole ring system using a robust, silica-supported palladium catalyst
Tyrrell, Elizabeth,Whiteman, Leon,Williams, Neil
experimental part, p. 829 - 835 (2009/07/25)
The use of a recyclable silica-supported palladium catalyst in Sonogashira couplings and indole syntheses using a range of functionalised substrates is described. The catalyst is shown to be both robust and versatile, effecting the synthesis of 2-phenylindole in quantitative yield without the need for N-protection, a copper co-catalyst, a base, or a solvent. Georg Thieme Verlag Stuttgart.
CuX2-mediated [4+2] benzannulation as a new synthetic tool for stereoselective construction of haloaromatic compounds
Isogai, Yukie,Menggenbateer,Nawaz Khan,Asao, Naoki
experimental part, p. 9575 - 9582 (2010/01/16)
The CuX2-mediated reaction of enynal units, including ortho-alkynylbenzaldehydes, with alkynes gives a variety of haloaromatic compounds stereoselectively in good to high yields. 2,2′-Binaphthyl skeletons are also readily prepared by the reacti
