52753-91-0Relevant academic research and scientific papers
A solvent- And catalyst-free tandem reaction: Synthesis, and photophysical and biological applications of isoindoloquinazolinones
Ali, Sk Asraf,Bera, Anirban,Ikbal, Mohammed,Manna, Susanta Kumar,Misra, Sandip,Saha, Amit,Samanta, Shubhankar
supporting information, p. 4324 - 4331 (2020/03/26)
An easy green synthetic approach for fused isoindoloquinazolinones has been developed under neat reaction (yields up to 91%) conditions. This new one-pot tandem methodology involves condensation of readily available anthranilamide with 3-(2-formylcycloalk
Copper Catalyzed One-Pot Three-Component Imination-Alkynylation-aza-Michael Sequence: Enantio- And Diastereoselective Syntheses of 1,3-Disubstituted Isoindolines and Tetrahydroisoquinolines
Das, Braja Gopal,Shah, Sadhna,Singh, Vinod K.
supporting information, p. 4981 - 4985 (2019/07/08)
An enantio- and diastereoselective syntheses of 1, 3-disubstituted isoindolines and tetrahydroisoquinolines via CuI-Pybox-diPh catalyzed one-pot imination-alkynylation-aza-Michael sequence has been reported. The three-component reaction produces one C-C and two C-N bonds sequentially with high yield (up to 92%), enantioselectivity (up to 99%), and diastereoselectivity (up to 9:1) in a single operation. Furthermore, the synthetic utility of the product has been demonstrated by LiAlH4 reduction of ester and hydrogenation of alkyne functionality without losing the stereoselectivity.
Rhodium-catalyzed ortho-C-H olefination of aromatic aldehydes employing transient directing strategy
Liu, Xi,Wang, Zhonghao,Chen, Qun,He, Ming-Yang,Wang, Liang
, (2018/02/07)
A Rhodium(III)-catalyzed ortho-C-H olefination of aromatic aldehydes in the presence of catalytic amount of TsNH2 has been developed. The in situ generated imine intermediate from aldehyde and TsNH2 worked as a transient directing gr
CoIII-Carbene Radical Approach to Substituted 1H-Indenes
Das, Braja Gopal,Chirila, Andrei,Tromp, Moniek,Reek, Joost N. H.,De Bruin, Bas
supporting information, p. 8968 - 8975 (2016/07/30)
A new strategy for the catalytic synthesis of substituted 1H-indenes via metalloradical activation of o-cinnamyl N-tosyl hydrazones is presented, taking advantage of the intrinsic reactivity of a CoIII carbene radical intermediate. The reaction uses readily available starting materials and is operationally simple, thus representing a practical method for the construction of functionalized 1H-indene derivatives. The cheap and easy to prepare low spin cobalt(II) complex [CoII(MeTAA)] (MeTAA = tetramethyltetraaza[14]annulene) proved to be the most active catalyst among those investigated, which demonstrates catalytic carbene radical reactivity for a nonporphyrin cobalt(II) complex, and for the first time catalytic activity of [CoII(MeTAA)] in general. The methodology has been successfully applied to a broad range of substrates, producing 1H-indenes in good to excellent yields. The metallo-radical catalyzed indene synthesis in this paper represents a unique example of a net (formal) intramolecular carbene insertion reaction into a vinylic C(sp2)-H bond, made possible by a controlled radical ring-closure process of the carbene radical intermediate involved. The mechanism was investigated computationally, and the results were confirmed by a series of supporting experimental reactions. Density functional theory calculations reveal a stepwise process involving activation of the diazo compound leading to formation of a CoIII-carbene radical, followed by radical ring-closure to produce an indanyl/benzyl radical intermediate. Subsequent indene product elimination involving a 1,2-hydrogen transfer step regenerates the catalyst. Trapping experiments using 2,2,6,6-tetra-methylpiperidine-1-oxyl (TEMPO) radical or dibenzoylperoxide (DBPO) confirm the involvement of cobalt(III) carbene radical intermediates. Electron paramagnetic resonance spectroscopic spin-trapping experiments using phenyl N-tert-butylnitrone (PBN) reveal the radical nature of the reaction.
Flexible, dicationic imidazolium salts for in situ application in palladium-catalysed Mizoroki–Heck coupling of acrylates under aerobic conditions
Milton, Marilyn Daisy,Garg, Parul
, p. 759 - 766 (2016/09/04)
The synthesis, characterization and in situ catalytic performance of new unsymmetric N,N′-disubstituted imidazolium-based dicationic salts in Mizoroki–Heck coupling of acrylates with aryl bromides under aerobic conditions are described. A series of flexible dicationic salts with varying steric and electronic properties were synthesized in good to excellent yields. All the salts were well characterized using spectroscopic techniques. X-ray diffraction analysis of two salts with the same dicationic backbone and different counter anions shows that the ligand adopts two different conformations which are influenced by the nature of the anion. Thus, the ligand is capable of changing its conformation according to the change in environment due to its flexible nature. All the synthesized imidazolium salts were found to be active in in situ palladium-catalysed Mizoroki–Heck coupling under aerobic conditions. Amongst the salts, the hydroxyl-functionalized imidazolium salt, incorporating the features of both bidentate chelating O,O ligand and carbene, shows the maximum catalytic activity. A variety of aryl and heteroaryl methyl and ethyl cinnamates were synthesized using these imidazolium salts as preligands. In addition, NMR studies confirm in situ generation of normal N-heterocyclic carbenes from the C-2 position of imidazol-2-ylidene ring. The mercury poisoning test was also performed to ascertain the nature of catalytically active palladium species. Aerobic conditions, low catalytic loading (0.5?mol%), shorter reaction times, broad functional group tolerance and good to excellent isolated yields are some of the significant features of the novel catalytic systems described here. Copyright
Biogenic synthesis of cellulose supported Pd(0) nanoparticles using hearth wood extract of Artocarpus lakoocha Roxb - A green, efficient and versatile catalyst for Suzuki and Heck coupling in water under microwave heating
Baruah, Diganta,Das, Ram Nath,Hazarika, Swapnali,Konwar, Dilip
, p. 73 - 80 (2015/10/06)
A simple, convenient and green protocol has been developed for the synthesis of cellulose supported Pd(0) nanoparticles (NPs) using hearth wood extract of Artocarpus lakoocha Roxb-as a bioreductant. Novel one-step method for the isolation of active bioreductant oxyresveratrol (2, 3′, 4, 5′-tetrahydroxy-trans-stilbene) present in the hearth wood extract of A. lakoocha Roxb is also disclosed. Synthesized cellulose supported Pd(0) NPs have been used as an efficient catalyst for Suzuki and Heck coupling reactions in water under microwave irradiation. The prepared Pd(0) NPs were characterized by Ultraviolet-visible (UV-vis), Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Transmission electron microscopy (TEM). The catalyst can be recycled up-to ten times without losing its activity significantly.
Simple Aza -conjugate addition methodology for the synthesis of isoindole nitrones and 3,4-dihydroisoquinoline nitrones
Peacock, Lucy R.,Chapman, Robert S. L.,Sedgwick, Adam C.,Bull, Steven D.,Mahon, Mary F.,Amans, Dominique
, p. 994 - 997 (2015/03/18)
Aryl-aldehydes containing ortho-substituted α,β-unsaturated carboxylic acid derivatives react with hydroxylamine to afford reactive N-hydroxy-carbinolamine intermediates that undergo intramolecular aza-conjugate addition reactions to afford isoindole nitrones and 3,4-dihydroisoquinoline nitrones in good yield. Conditions have been developed to reduce these isoindole nitrones to their corresponding hydroxylamine, enamine, and amine derivatives. Isoindole nitrones react with dimethyl acetylenedicarboxylate (DMAD) via a [4 + 2]-cycloaddition/deamination pathway to afford substituted naphthalene derivatives, while 3,4-dihydroisoquinoline nitrones react with DMAD via a [1,3]-dipolar cycloaddition pathway to afford tricyclic heteroarenes.
NHC-catalyzed oxidative cyclization reaction for the synthesis of 3-substituted phthalides
Youn, So Won,Song, Hyoung Sub,Park, Jong Hyub
supporting information, p. 2388 - 2393 (2014/04/03)
An efficient NHC-catalyzed domino oxidation/oxa-Michael addition reaction of 2-alkenylbenzaldehydes has been developed to afford 3-substituted phthalides bearing a C3-stereogenic center with a broad substrate scope and wide functional group tolerance. The preliminary results of the asymmetric process have been provided as well. the Partner Organisations 2014.
P4S10 and Na2S-mediated novel annulation routes to c-fused thiophenes
Yasmin, Nasima,Ghosh, Munmun,Ray, Jayanta K.
, p. 19932 - 19938 (2014/05/20)
Two efficient hetero-annulation protocols have been developed for the synthesis of stable substituted c-fused thiophene derivatives with moderate to high yield. 3-(2-formyl-phenyl)-acrylic acid esters afforded benzo[c]thiophenes in the presence of phospho
Palladium(II)-catalyzed ortho -olefination of arenes applying sulfoxides as remote directing groups
Wang, Binjie,Shen, Chuang,Yao, Jinzhong,Yin, Hong,Zhang, Yuhong
, p. 46 - 49 (2014/01/23)
A novel palladium-catalyzed ortho-C(sp2)-H olefination protocol has been developed by the use of sulfoxide as the directing group. Importantly, relatively remote coordination can be accessed to achieve the ortho olefination of benzyl, 2-arylethyl, and 3-arylpropenyl sulfoxide substrates, and the olefinated sulfoxide can be easily transformed to other functionalities.
