126829-31-0Relevant articles and documents
Design, synthesis and application of triazole ligands in suzuki miyaura cross coupling reaction of aryl chlorides
Jabeen, Sobia,Khera, Rasheed Ahmad,Iqbal, Javed,Asgher, Muhammad
, (2020/01/28)
DFT calculations have been demonstrated to be a valuable tool for the mechanistic study of reaction which is difficult to acquire from pure experimental techniques. Structural, electronic and coordination aspects of synthesized triazole ligands were investigated theoretically by structure optimization on Gaussian 09 package by DFT approach at B3LYP/6-31G (d, p). HOMO-LUMO energy gaps correlated to its chemical reactivity and this information applied to interpret the role of ligand in the formation of ligand-metal complex. Electron rich environment around the triazole core stabilized the HOMO orbital and made these electrons available to form complex with Pd centre. The DFT calculations provide a plausible mechanism for the reaction that is consistent with the available experimental facts. A series of triazole ligands have been synthesized via efficient 1,3-dipolar cycloaddition of readily available azide and alkynes for coordination to Pd centre. Characterization of all the synthesized compounds was done by FTIR, 1H NMR, 13C NMR and HRMS. Their ligand-Pd complexes provided excellent yields in the Suzuki-Miyaura coupling reactions (up to 92% yield) of unactivated aryl chlorides. Ligand 4-(2,6-dimethoxyphenyl)-1-phenyl-1H-1,2,3-triazole (L2) was found to be most effective ligand because of electron donating 2,6 dimethoxy phenyl moiety attached to triazole ring at 4-position that facilitated the formation of electron rich ligand-catalyst complex. The complex favoured the oxidative addition step of Pd across the aryl chloride substrate and thus allowed for the development of highly active ligand-catalyst system for Suzuki reaction. During computational analysis, 4-(2,6-dimethoxyphenyl)-1-phenyl-1H-1,2,3-triazole (L2) also showed lowest band gap due to electron rich distribution pattern on the HOMO that are involve in ligand-Pd complex formation. Conclusively, these triazoles ligands were found to be more competent and attractive for palladium catalyst because of simplistic pathway for the synthesis of triazole motif and the ease of individual tuning of the substituents on triazole core or exocyclic to it.
Synthesis of Triazole Click Ligands for Suzuki-Miyaura Cross-Coupling of Aryl Chlorides
Jabeen,Khera,Iqbal,Asgher
, p. 1416 - 1422 (2019/11/03)
A series of new triazole ligands has been synthesized via copper-catalyzed cycloaddition reaction of readily available azides and alkynes. The synthesized compounds were characterized by FTIR, 1H and 13C NMR, and high-resolution mass spectra. The ligands provided excellent yields (up to 92%) in the palladium-catalyzed Suzuki-Miyaura cross coupling of unactivated aryl chlorides with phenylboronic acid. 1-Benzyl-4-(2,6-dimethoxyphenyl)-lH-1,2,3-triazole was found to be the most effective ligand due to the presence of electron-donating 2,6-dimethoxyphenyl substituent, which made it possible to develop a highly active ligand-catalyst system for the Suzuki reaction of aryl chlorides.
Reactivity switch enabled by counterion: Highly chemoselective dimerization and hydration of terminal alkynes
Xu, Caixia,Du, Weiyuan,Zeng, Yi,Dai, Bin,Guo, Hao
, p. 948 - 951 (2014/03/21)
A counterion-controlled reactivity tuning in Pd-catalyzed highly chemoselective and regioselective dimerization and hydration of terminal alkynes is reported. The use of acetate as counterion favors the formation of an alkenyl alkynyl palladium intermediate which forms hitherto less reported 1,3-diaryl-substituted conjugated enynes after reductive elimination. Using chloride, which is a better leaving group, leads to anion exchange on the alkenylpalladium intermediate with hydroxide which after reductive elimination and tautomerization delivered the hydration products.
CRYSTALLINE 1H-1,2,3-TRIAZOL-5-YLIDENES
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Page/Page column 41, (2011/11/30)
The present invention provides novel and stable crystalline 1H-1,2,3 triazolium carbenes and metal complexes of 1H-1,2,3 triazolium carbenes. The present invention also provides methods of making 1H-1,2,3 triazolium carbenes and metal complexes of 1H-1,2,
2-Amino-4-methyl-5-phenylethyl substituted-7-N-benzyl-pyrrolo[2,3-d] pyrimidines as novel antitumor antimitotic agents that also reverse tumor resistance
Gangjee, Aleem,Namjoshi, Ojas A.,Keller, Staci N.,Smith, Charles D.
, p. 4355 - 4365 (2011/08/09)
Gangjee et al. recently reported a novel series of 2-amino-4-methyl-5- phenylethyl substituted-7-benzyl-pyrrolo[2,3-d]pyrimidines, some of which exhibited two digit nanomolar antitumor and antimitotic activity and were not subject to P-glycoprotein (Pgp)
Regioselective hydrostannation of highly hindered arylalkynes under ortho-directing effects
Hamze, Abdallah,Le Menez, Patrick,Provot, Olivier,Morvan, Estelle,Brion, Jean-Daniel,Alami, Mouad
experimental part, p. 8698 - 8706 (2010/11/18)
Palladium-catalyzed hydrostannation reactions of ortho-disubstituted arylalkynes were achieved with total stereo- and regio-selectivity in THF at room temperature. The regioselectivity was found to be under the control of the ortho-substituents (ortho-dir
Ortho, ortho′-Substituted KITPHOS monophosphines: Highly efficient ligands for palladium-catalyzed C-C and C-N bond formation
Doherty, Simon,Knight, Julian G.,McGrady, John P.,Ferguson, Alexandra M.,Ward, Nicholas A. B.,Harrington, Ross W.,Clegg, William
supporting information; experimental part, p. 201 - 211 (2010/06/20)
ortho, ortho′-Substitution of the phosphinoalkyne-derived aryl ring in KITPHOS (11-dicyclohexylphosphino-12-phenyl-9,10-ethenoanthracene) monophosphines enhances the performance of this class of ligand in palladium-catalyzed Suzuki-Miyaura cross-couplings and BuchwaldHartwig aminations, compared with their unsubstituted and mono-substituted counterparts. An alternative complementary synthesis of KITPHOS monophosphines has been developed and two new members of this family, 2,6-Me2-KITPHOS [11-dicyclohexylphosphino-12-(2,6-dimethylphenyl)-9,10-ethenoanthracene] and 2,6-(MeO)2-KITPHOS [11-dicyclohexylphosphino-12-(2,6-dimethoxyphenyl)-9,10-ethenoanthracene], have been prepared; palladium complexes of both are highly efficient catalysts for C - C and C - N bond formation with a range of electron-rich and electron-poor aromatic chlorides as well as heteroaryl chlorides.
Photochemical and photophysical characteristics in the excited state properties of methoxy-substituted enediynes
Yoshimura, Nao,Momotake, Atsuya,Shinohara, Yoshihiro,Nishimura, Yoshinobu,Arai, Tatsuo
, p. 174 - 175 (2008/09/18)
Effects of methoxy substituent on the phenyl ring of cis isomer of enediynes were explored. All the cis isomers exhibited fluorescence emission with moderate efficiency. Furthermore, the ortho-substituted compounds showed red shift of the fluorescence emission even though crystallographic analysis suggests that the single bond connecting the phenyl ring and carbon-carbon triple bond takes considerably twisted conformation. Copyright
Synthesis and structure-activity relationship of histone deacetylase (HDAC) inhibitors with triazole-linked cap group
Chen, Po C.,Patil, Vishal,Guerrant, William,Green, Patience,Oyelere, Adegboyega K.
, p. 4839 - 4853 (2008/12/21)
Histone deacetylase (HDAC) inhibition is a recent, clinically validated therapeutic strategy for cancer treatment. Small molecule HDAC inhibitors identified so far fall in to three distinct structural motifs: the zinc-binding group (ZBG), a hydrophobic linker, and a recognition cap group. Here we report the suitability of a 1,2,3-triazole ring as a surface recognition cap group-linking moiety in suberoylanilide hydroxamic acid-like (SAHA-like) HDAC inhibitors. Using "click" chemistry (Huisgen cycloaddition reaction), several triazole-linked SAHA-like hydroxamates were synthesized. Structure-activity relationship revealed that the position of the triazole moiety as well as the identity of the cap group markedly affected the in vitro HDAC inhibition and cell growth inhibitory activities of this class of compounds.
Direct diazo-transfer reaction on β-lactam: Synthesis and preliminary biological activities of 6-triazolylpenicillanic acids
Chen, Po C.,Wharton, Rebekah E.,Patel, Pratiq A.,Oyelere, Adegboyega K.
, p. 7288 - 7300 (2008/03/28)
In this study we report the first example of a direct diazo-transfer reaction on readily available 6-aminopenicillanates to give 6-azidopenicillanates in high yield. Subsequent Cu(I)-catalyzed Huisgen cycloaddition between these 6-azidopenicillanates and assorted terminal alkynes facilely furnished 6-triazolylpenicillanic acids. Preliminary biological screening indicates that these triazolylpenicillanic acids possess low to moderate antibacterial activities.
