- Visible-light induced copper(i)-catalysed denitrogenative oxidative coupling of hydrazinylpyridines with terminal alkynes
-
Visible light mediated copper catalysed denitrogenative oxidative coupling of 2-hydrazinopyridines with terminal alkynes to form 2-(alkyl/arylethynyl) pyridines in the presence of O2 at room temperature is reported with 42 examples. This is the first report on visible light stimulated N2 elimination by an in situ generated copper(ii) superoxo/peroxo complex. N2 and water are the only by-products. The green chemistry metrics evaluation signifies that the current method is ecofriendly and economically feasible. This method allows the green synthesis of mGluR5 receptor antagonists, 2-methyl-6-(phenylethynyl)pyridine (MPEP) and 2-((3-methoxyphenyl)ethynyl)-6-methylpyridine (M-MPEP).
- Charpe, Vaibhav Pramod,Hande, Aniket A.,Sagadevan, Arunachalam,Hwang, Kuo Chu
-
supporting information
p. 4859 - 4864
(2018/11/21)
-
- Mononuclear and dinuclear heteroleptic Cu(I) complexes based on pyridyl-triazole and DPEPhos with long-lived excited-state lifetimes
-
A mononuclear and two dinuclear heteroleptic Cu(I) complexes have been successfully prepared, using the chelating bis [(2-diphenylphosphino)phenyl] ether (DPEPhos) and pyrid-2′-yl-1H-1,2,3-triazole as N?N chelating ligands. They show good luminescence in solution at room temperature with long-lived excited states. Furthermore, bimolecular quenching experiments of these new complexes with the catalyst Ni(cyclam)Cl2 encourage the use of such compounds as photosensitizers for the photoreduction of carbon dioxide.
- Bizzarri, Claudia,Arndt, Andreas P.,Kohaut, Stephan,Fink, Karin,Nieger, Martin
-
p. 140 - 149
(2018/07/25)
-
- Transformation of Carbonyl Compounds into Homologous Alkynes under Neutral Conditions: Fragmentation of Tetrazoles Derived from Cyanophosphates
-
Cyanophosphates (CPs) can be easily prepared from either ketones or aldehydes, and their reaction with NaN3-Et3N·HCl results in the formation of azidotetrazoles. Under microwave irradiation, successive fragmentation of the azidotetrazoles generates alkylidene carbenes that undergo [1,2]-rearrangement and are transformed into homologous alkynes. Treatment of ketone-derived CPs with TMSN3 and Bu2SnO as catalyst in toluene at reflux directly yields the corresponding internal alkynes, whereas the reaction of aldehyde-derived CPs with NaN3-Et3N·HCl in THF at reflux or TMSN3-Bu2SnO (cat.) in toluene at reflux provides homologous terminal alkynes in good yields. These reactions take place under neutral conditions and can be successfully extended to obtain alkynes that are not usually accessible from the corresponding carbonyl compounds by the Ohira-Bestmann or Shioiri procedures, which require basic conditions.
- Yoneyama, Hiroki,Numata, Masahiro,Uemura, Kenji,Usami, Yoshihide,Harusawa, Shinya
-
p. 5538 - 5556
(2017/06/07)
-
- Palladium-catalyzed deacetonative coupling of aryl propargylic alcohols with aryl chlorides in water
-
A highly efficient and green process for palladium-catalyzed deacetonative coupling of aryl propargylic alcohols with aryl chlorides has been developed. The reaction occurs smoothly in neat water with 2 mol% PdCl2 as catalyst, and various synthetically useful functional groups, including ether, aldehyde, ketone, and heterocyclics, are well tolerated. Moreover, the reaction could proceed through a consecutive Sonogashira/deacetonative process using 2-methyl-3-butyn-2-ol and aryl chlorides as coupling partners, affording the symmetric alkynes in good yields.
- Chang, Feng,Liu, Yanping
-
supporting information
p. 961 - 967
(2017/05/04)
-
- Simultaneous rapid reaction workup and catalyst recovery
-
By combining reaction work-up and catalyst recovery into a simple filtration procedure we have developed a substantially faster technique for organic synthesis. Our protocol eliminates the time-consuming conventional liquid-liquid extraction and is capable of parallelization and automation. Additionally, it requires only minimal amounts of solvent.
- Lu, Zhichao,Hetman, Zofia,Hammond, Gerald B.,Xu, Bo
-
supporting information
p. 5769 - 5772
(2016/11/06)
-
- Phosphine-free palladium-catalyzed decarboxylative coupling of alkynylcarboxylic acids with aryl and heteroaryl halides
-
We herein report the design and development of a carboxyamido/carbene ligand and its Pd-complex for the decarboxylative coupling of alkynylcarboxylic acids with aryl and heteroaryl halides to afford arylalkynes. Copyright
- Reddy, Police Vishnuvardhan,Srinivas, Pottabathula,Annapurna, Manne,Bhargava, Suresh,Wagler, Jorg,Mirzadeh, Nedaossadat,Kantam, Mannepalli Lakshmi
-
supporting information
p. 705 - 710
(2013/04/23)
-
- Double arylation of diynes and alkynylation of functionalized heteroaryl halides by a practical heck reaction in an ionic liquid
-
The efficient palladium-catalyzed alkynylation of electron-rich bromoheteroarenes, incorporating deactivating electron-donating methyl and methoxy groups, and the (hetero)arylation of diynes, take place in the imidazolium ionic liquid [BMIM][BF4/sub
- Saleh, Samer,Picquet, Michel,Meunier, Philippe,Hierso, Jean-Cyrille
-
experimental part
p. 2844 - 2848
(2012/01/11)
-
- A novel palladium-catalyzed cross-coupling of thiomethylated alkynes with functionalized organozinc reagents
-
A range of methylthio-substituted acetylenes undergo smooth palladium-catalyzed cross-coupling reactions with functionalized aryl-, heteroaryl-, and alkylzinc reagents using the Pd(OAc)2/DPE-Phos catalytic system at 25 or 50 C without the need for copper salts. Georg Thieme Verlag Stuttgart.
- Melzig, Laurin,Stemper, Jeremy,Knochel, Paul
-
experimental part
p. 2085 - 2091
(2010/08/19)
-
- Synthesis and biological evaluation of fenobam analogs as mGlu5 receptor antagonists
-
Optimization of affinity and microsomal stability led to identification of the potent, metabolically stable fenobam analog 4l. Robust in vivo efficacy of 4l was demonstrated in four different models of anxiety. Additionally, a ligand based pharmacophore a
- Jaeschke, Georg,Porter, Richard,Buettelmann, Bernd,Ceccarelli, Simona M.,Guba, Wolfgang,Kuhn, Bernd,Kolczewski, Sabine,Huwyler, Joerg,Mutel, Vincent,Peters, Jens-Uwe,Ballard, Theresa,Prinssen, Eric,Vieira, Eric,Wichmann, Juergen,Spooren, Will
-
p. 1307 - 1311
(2007/10/03)
-
- Synthesis and receptor assay of aromatic-ethynyl-aromatic derivatives with potent mGluR5 antagonist activity
-
Noncompetitive antagonists of the human metabotropic glutamate receptor subtype 5 (mGluR5) have been implicated as potential therapeutics for the treatment of a variety of nervous system disorders, including pain, anxiety, and drug addiction. To discover novel noncompetitive antagonists to the mGluR5, we initiated an SAR study around the known lead compounds MPEP and M-MPEP. Our results pointed out the critical role of the para position of the two aromatic rings, which leads to inactive products and permitted the discovery of potent mGluR5 antagonists (e.g., 16, 25, 28, 34 IC50 = 13.5, 11.9, 21, 15 nM, respectively). Noncompetitive antagonists of the human metabotropic glutamate receptor subtype 5 (mGluR5) have been implicated as potential therapeutics for the treatment of a variety of nervous system disorders, including pain, anxiety, and drug addiction. To discover novel noncompetitive antagonists to the mGluR5, we initiated an SAR study around the known lead compounds MPEP and M-MPEP. Our results pointed out the critical role of the para position of the two aromatic rings, which leads to inactive products and permitted the discovery of potent mGluR5 antagonists (e.g., 16, 25, 28, 34 IC50 = 13.5, 11.9, 21, 15 nM, respectively).
- Alagille, David,Baldwin, Ronald M.,Roth, Bryan L.,Wroblewski, Jarda T.,Grajkowska, Ewa,Tamagnan, Gilles D.
-
p. 197 - 209
(2007/10/03)
-
- Copper-free palladium-catalyzed sonogashira-type coupling of aryl halides and 1-aryl-2-(trimethylsilyl)acetylenes
-
A one-pot procedure for the direct coupling of 1-aryl-2- trimethylsilylacetylenes with aryl halides to give diaryl acetylenes is reported. The procedure does not involve the use of copper(I) iodide. Improvement in reaction yields has been obtained by replacing conventional oil bath heating with the use of microwave dielectric heating.
- S?rensen, Ulrik S.,Pombo-Villar, Esteban
-
p. 2697 - 2703
(2007/10/03)
-
- A Novel Ethynylation of Pyridines by Reissert-Henze Type Reaction
-
Reaction of N-benzoyloxypyridinium chloride, Reissert-Henze salt, with silver acetylide gave the pyridine ethynylated selectively at 2-position.The reaction is applicable to various substituted pyridines and pyridine homologs.
- Nishiwaki, Nagatoshi,Minakata, Satoshi,Komatsu, Mitsuo,Ohshiro, Yoshiki
-
p. 773 - 776
(2007/10/02)
-