- L -(-) -Quebrachitol as a Ligand for Selective Copper(0)-Catalyzed N-Arylation of Nitrogen-Containing Heterocycles
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l-(-)-Quebrachitol (QCT) has been found as a ligand of copper powder for selective N-arylation of nitrogen-containing heterocycles with aryl halides. Furthermore, another potential catalytic system (copper powder/QCT/t-BuOK) was successfully adapted to unactivated aryl chlorides.
- Zhou, Qifan,Du, Fangyu,Chen, Yuanguang,Fu, Yang,Sun, Wenjiao,Wu, Ying,Chen, Guoliang
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p. 8160 - 8167
(2019/06/28)
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- Interacting networks of purely organic spin-1/2 dimers
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In the present study we report the synthesis of some novel nitronyl nitroxide biradical systems 1-4c with various π-bridges between the radical centres. UV-Vis, IR, EPR and X-ray diffraction studies, along with MS and NMR data where appropriate, are described. Magnetic measurements revealed that the biradicals 1c, 3c and 4c exhibit a moderately strong antiferromagnetic intra-molecular exchange, whereas nitroxide 2c shows a significantly higher exchange coupling, which can only be explained by the presence of strong inter-molecular interactions. From DFT calculations performed on the basis of the X-ray crystal structure of compound 4c, a theoretical value of the intra-dimer coupling constant Jintra = -8.6 K is obtained. Direct proof also for inter-molecular arrangement with Jinter ~ -2 K was provided by the low temperature AC studies of biradical 4c. According to the magnetic characterization, the nitronyl biradical 4c is a promising candidate for a purely organic-based low-dimensional quantum magnet. This journal is the Partner Organisations 2014.
- Borozdina, Yulia B.,Mostovich, Evgeny,Enkelmann, Volker,Wolf, Bernd,Cong, Pham T.,Tutsch, Ulrich,Lang, Michael,Baumgarten, Martin
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p. 6618 - 6629
(2014/08/18)
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- N-aryl pyrazoles: DFT calculations of CH acidity and deprotonative metallation using a combination of lithium and zinc amides
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A series of N-aryl and N-heteroaryl pyrazoles have been deproto-metallated using a 2,2,6,6-tetramethylpiperidino-based mixed lithium-zinc combination. Mono-, di-, and tri-iodides have been obtained after subsequent trapping with iodine, depending on the s
- Chevallier, Floris,Halauko, Yury S.,Pecceu, Christelle,Nassar, Ibrahim F.,Dam, To Uyen,Roisnel, Thierry,Matulis, Vadim E.,Ivashkevich, Oleg A.,Mongin, Florence
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scheme or table
p. 4671 - 4684
(2011/07/07)
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- Method of forming a carbon-carbon or carbon-heteroatom linkage
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The invention relates to a method of creating a carbon-carbon or carbon-heteroatom linkage by reacting an unsaturated compound bearing a leaving group and a nucleophilic compound. More specifically, the invention relates to the creation of a carbon-nitrogen linkage involving the arylation of nitrogenous organic derivatives. The inventive method consists in creating a carbon-carbon or carbon-heteroatom linkage by reacting an unsaturated compound bearing a leaving group and a nucleophilic compound providing a carbon atom or a heteroatom (HE) capable of being substituted for the leaving group, thereby creating a C—C or C-HE linkage. The invention is characterised in that the reaction is carried out in the presence of an effective quantity of a catalyst based on copper and at least one ligand comprising at least one imine function and at least one additional nitrogen atom as chelating atoms
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Page/Page column 26
(2010/02/14)
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- Mild conditions for copper-catalysed N-arylation of pyrazoles
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Copper-catalysed N-arylation of pyrazoles with aryl or heteroaryl bromides or iodides, which can include functional substituents, was performed under the mildest conditions yet described, with excellent yields and selectivity, by the use as catalyst of a combination of cuprous oxide with a set of inexpensive, chelating oxime-type ligands not previously known to promote such reactions. Other original bi-, tri- or tetradentate ligands providing nitrogen and/or oxygen as chelating atoms were also successfully tested in this type of arylation. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).
- Cristau, Henri-Jean,Cellier, Pascal P.,Spindler, Jean-Francis,Taillefer, Marc
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p. 695 - 709
(2007/10/03)
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- Process for arylating or vinylating or alkynating a nucleophilic compound
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The present invention concerns a process for arylating or vinylating or alkynating a nucleophilic compound. More particularly, the invention concerns arylating nitrogen-containing organic derivatives. The arylating or vinylating or alkynating process of the invention consists of reacting a nucleophilic compound with a compound carrying a leaving group and is characterized in that the reaction is carried out in the presence of an effective quantity of a catalyst based on a metallic element M selected from groups (VIII), (Ib) and (IIb) of the periodic table and at least one ligand comprising at least one imine function and at least one supplemental nitrogen atom as the chelating atoms.
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- Heterocyclopolyaromatics, X: About the First Cyclohexaaromatic Compound with 'Face-to-Face' Arrangement of Two Aromatic Ringmembers
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Oxidative coupling with CuCl2 of dilithiated 1,4-di(1-pyrazolyl)benzene afforded 8,11:20,23-diethenotetrapyrazolotetraazacyclohexadecine (4, yield 48percent).The face-to-face arrangement of the benzene rings
- Lexy, Herbert,Kauffmann, Thomas
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p. 2749 - 2754
(2007/10/02)
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