The Experts below are selected from a list of 17013 Experts worldwide ranked by ideXlab platform
Shovan Mondal - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Polycyclic Sultamsby Palladium-Catalyzed Intramolecular Cyclization
Synthesis, 2009Co-Authors: Krishna C. Majumdar, Shovan MondalAbstract:A practical and high-yielding method for the synthesis of new sultams from readily available sulfonamides, 1-naphthylamine, and 2-halobenzyl bromides is reported. A variety of tricyclic, tetra-cyclic, and pentacyclic sultams have been prepared via palladium-catalyzed, ligand-free Intramolecular Cyclization. Detailed mechanistic studies of the reaction pathway are also described.
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Synthesis of tricyclic and tetracyclic sultones by Pd-catalyzed Intramolecular Cyclization
Tetrahedron Letters, 2009Co-Authors: Krishna C. Majumdar, Shovan Mondal, Debankan GhoshAbstract: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.
Krishna C. Majumdar - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Polycyclic Sultamsby Palladium-Catalyzed Intramolecular Cyclization
Synthesis, 2009Co-Authors: Krishna C. Majumdar, Shovan MondalAbstract:A practical and high-yielding method for the synthesis of new sultams from readily available sulfonamides, 1-naphthylamine, and 2-halobenzyl bromides is reported. A variety of tricyclic, tetra-cyclic, and pentacyclic sultams have been prepared via palladium-catalyzed, ligand-free Intramolecular Cyclization. Detailed mechanistic studies of the reaction pathway are also described.
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Synthesis of tricyclic and tetracyclic sultones by Pd-catalyzed Intramolecular Cyclization
Tetrahedron Letters, 2009Co-Authors: Krishna C. Majumdar, Shovan Mondal, Debankan GhoshAbstract: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.
Steven P. Armes - One of the best experts on this subject based on the ideXlab platform.
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Extent of Intramolecular Cyclization in RAFT-synthesized methacrylic branched copolymers using 13C NMR spectroscopy
Polymer Chemistry, 2015Co-Authors: Julien Rosselgong, Steven P. ArmesAbstract:Recently, we reported using 1H NMR spectroscopy to assess the degree of Intramolecular Cyclization in a series of soluble methacrylic branched copolymers (see J. Rosselgong and S. P. Armes, Macromolecules, 2012, 45, 2731–2737). The key to success in addressing this long-standing problem in polymer science was the selection of a suitable disulfide-based dimethacrylate as the branching comonomer, which was statistically copolymerized with methyl methacrylate using reversible addition-fragmentation chain transfer (RAFT) polymerization. In this earlier work, estimation of the degree of Intramolecular Cyclization required peak deconvolution of the relevant thiamethylene proton signals. In the present work, we show that quantitative 13C NMR spectroscopy can also be utilized to determine the Intramolecular Cyclization for the same series of methacrylic copolymers via peak deconvolution of the oxymethylene carbon signals. Although this technique requires long spectral accumulation times, it offers superior resolution compared to 1H NMR spectroscopy and hence may ultimately enable this analytical approach to be applied to less esoteric divinyl comonomers.
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Quantification of Intramolecular Cyclization in Branched Copolymers by 1H NMR Spectroscopy
Macromolecules, 2012Co-Authors: Julien Rosselgong, Steven P. ArmesAbstract:Statistical copolymerization of a monovinyl with a divinyl monomer leads to macroscopic gels, microgels, or soluble branched copolymers, depending on the precise reaction conditions. This approach is widely used for the manufacture of soft contact lenses and also to prepare various biomedical hydrogels for the separation and purification of proteins, DNA, etc. According to Flory–Stockmayer theory, gelation should occur in such copolymerizations if there is more than 0.50 fully reacted divinyl comonomer per primary chain. However, many experimental studies indicate significant deviations from this classical theory, which are generally believed to be due to wastage of the divinyl comonomer via Intramolecular Cyclization. Unfortunately, experimental verification of this side reaction has proven elusive for the past seven decades. In the present study, we use a disulfide-based cleavable bifunctional comonomer to undertake the first experimental quantification of the extent of Intramolecular Cyclization in non...
Dewen Dong - One of the best experts on this subject based on the ideXlab platform.
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Triflic Anhydride Promoted Intramolecular Cyclization of N-Aryl Cinnamides: Access to Polysubstituted Quinolin-2(1H)-ones
Synthesis, 2017Co-Authors: Qian Bo-zhang, Peng Huang, Rui Zhang, Jingwen Yuan, Yongjiu Liang, Dewen DongAbstract:A facile and efficient synthesis of polysubstituted quinolin-2(1 H )-ones is developed via Intramolecular Cyclization of readily available N -aryl cinnamides promoted by triflic anhydride in N , N -dimethyl trifluoroacetamide (DTA) under mild conditions.
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bf3 et2o mediated Intramolecular Cyclization of unsaturated amides convenient synthesis of dihydroquinolin 2 one bf2 complexes
RSC Advances, 2014Co-Authors: Xu Liu, Qian Bo-zhang, Rui Zhang, Yongjiu Liang, Xiaoqing Xin, Ning Zhang, Dewen DongAbstract:A facile and efficient synthesis of substituted dihydropyridone–BF2 complexes is developed via Intramolecular Cyclization of α-acyl acrylamides and α-acyl cinnamamides mediated by BF3·Et2O.
Caterina Zoni - One of the best experts on this subject based on the ideXlab platform.
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Regioselectivity on the palladium-catalyzed Intramolecular Cyclization of indole derivatives.
The Journal of organic chemistry, 2003Co-Authors: Giorgio Abbiati, Egle M. Beccalli, Gianluigi Broggini, Caterina ZoniAbstract:Indole 2-carboxamide derivatives 4 underwent palladium-catalyzed Intramolecular Cyclization reactions to afford β-carbolinones or pyrazino[1,2-a]indoles according to different reaction pathways. The complete regioselectivity of the reactions was obtained in different reaction conditions.
