Review
Chemistry, Applied
Roman S. Malykhin, Alexey Yu Sukhorukov
Summary: The review summarizes recent advances in the synthesis of C2-halogenated nitrogen heterocycles via nucleophilic halogenation of corresponding N-oxides and its application in pharmaceutical synthesis. It provides a practical guide based on extensive literature analysis to help practitioners choose optimal reagents/conditions for nucleophilic halogenation of N-heterocycles of different types. The bibliography contains 199 references.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Pham Duy Quang Dao, Chan Sik Cho
Summary: A class of trinuclear N-fused hybrid scaffolds, benzo[4,5]imidazo[1,2-a]benzo[4,5]imidazo[1,2-c]quinazolines and -pyrimidines, were successfully synthesized in good yields using a microwave-assisted coupling and cyclization process with 2-(2-Bromoaryl)- and 2-(2-bromovinyl)benzimidazoles as building blocks. The reaction is believed to proceed through an initial C(sp(2))-N coupling followed by a nucleophilic aromatic substitution (SNAr) and cyclization, resulting in the extrusion of alcohols.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Vasiliy M. Muzalevskiy, Zoia A. Sizova, Valentine G. Nenajdenko
Summary: In this study, a series of derivatives of 2-trifluoromethylindole were successfully synthesized through halogenation and base-catalyzed reactions, and the high synthetic utility of these compounds in reactions with various nucleophiles was demonstrated.
Article
Chemistry, Multidisciplinary
Adam N. Barrett, Martin Diefenbach, Mary F. Mahon, Vera Krewald, Ruth L. Webster
Summary: In this study, gram-scale quantities of 2,4,6-tris(triphenylmethyl)-Dewar-1,3,5-triphosphabenzene were synthesized using an alkyne cyclotrimerization regime. It was found that this compound can undergo rearrangement and phosphorus migration reactions to form ring-contracted species. Additionally, novel crystallographically characterized products of other transformations were reported.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Applied
Alexander Garay-Talero, Paola Acosta-Guzman, Diego Gamba-Sanchez
Summary: This manuscript presents a regioselective chlorination of arenes, yielding almost exclusively the monochlorinated product. It tolerates a wide range of functional groups and substituted aromatic rings, and demonstrates the utilization of chlorosulfonium salts as the chlorinating agent, avoiding the formation of organic byproducts.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Physical
Jaume Rostoll-Berenguer, Gonzalo Blay, Jose R. Pedro, Carlos Vila
Summary: Financial support is acknowledged from grant PID2020-116944GB funded by MCIN/AEI/10.13039/501100011033, and by ERDF A way of making Europe and CIAICO/2021/147 funded by Conselleria d'Innovacio, Universitat, Ciencia i Societat Digital. J.R.-B. thanks the Ministerio de Ciencia, Innovacion y Universidades for a FPU predoctoral contract (FPU17/00688). C.V. thanks the RyC contract (RYC-2016-20187) funded by MCIN/AEI/10.13039/501100011033 and by European Union NextGeneration EU/PRTR. Access to NMR, MS, and X-ray facilities from the Servei Central de Suport a la Investigacio Experimental (SCSIE)-UV is also acknowledged.
Article
Chemistry, Multidisciplinary
Gen Li, Marissa N. Lavagnino, Siraj Z. Ali, Shicheng Hu, Alexander T. Radosevich
Summary: A synthetic method for the reductive transformation of nitroarenes into ortho-aminated and-annulated products is reported, which involves deoxygenation and ring expansion reactions to generate functionalized products.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Organic
Jacob P. Norman, Nathaniel G. Larson, Emily D. Entz, Sharon R. Neufeldt
Summary: A highly selective method for cross-coupling reactions at the C4 position of 2,4-dichloropyridines was developed using a sterically hindered N-heterocyclic carbene ligand. The reaction showed high selectivity and broad scope, allowing for the formation of C4-C(sp2) and C4-C(sp3) bonds using organoboron, -zinc, and -magnesium reagents. Ligand-free conditions were also found to enhance the selectivity of the Suzuki coupling reaction by an order of magnitude, enabling the first C5-selective cross-couplings of 2,5-dichloropyridine and 2,5-dichloropyrimidine.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Review
Polymer Science
Silvestre Bongiovanni Abel, Evelina Frontera, Diego Acevedo, Cesar A. Barbero
Summary: This study summarizes the use of organic chemical reactions to functionalize preformed conducting polymers (CPs), focusing on polyaniline (PANI), polypyrrole (PPy), and polythiophene (PT), as well as limited work on other CPs. Two approaches have been taken for the functionalization: direct reactions on the CP chains and reaction with substituted CPs bearing reactive groups. Electrophilic aromatic substitution and nucleophilic conjugate addition are the main reaction mechanisms involved. The improved properties achieved by functionalization of different polymers are also discussed.
Article
Chemistry, Multidisciplinary
Hongjian Wang, Yonghong Ruan, Yu-Mei Lin, Haiping Xia
Summary: The direct C-H amidation or imidation of metallaaromatics with N-bromoamides or imides under mild conditions leads to the formation of a family of N-functionalized metallapentalyne derivatives. A unique 1,5-bromoamidated species identified serves as a sigma(H)-adduct intermediate in a nucleophilic aromatic substitution. The 1,5-addition of electrophilic and nucleophilic moieties into the metallaaromatic framework demonstrates a novel pathway different from the typical radical process of arene C-H amidation involving N-haloamide reagents.
Article
Chemistry, Applied
Surajit Duari, Subrata Biswas, Arnab Roy, Srabani Maity, Abhishek Kumar Mishra, Aguinaldo R. Souza, Asma M. Elsharif, Nelson H. Morgon, Srijit Biswas
Summary: In this study, a catalytic synthetic strategy was developed to access various N-functionalized heterocyclic derivatives. The reaction involves the direct nucleophilic substitution of alcohols followed by X to N alkyl group migration. Methyl trifluoromethanesulfonate was found to be an efficient catalyst for this reaction. The mechanism was elucidated through experiments and DFT calculations.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Organic
Dmytro I. Sierov, Illia V. Dzhulai, Kateryna I. Siryk, Kostiantyn V. Shvydenko, Tetiana I. Shvydenko, Kostiantyn Nazarenko, Aleksandr Kostyuk, Oleksandr S. Liashuk, Oleksandr O. Grygorenko
Summary: A systematic study on the SnAr reaction of halogenated fluoropyridines with (hetero)aliphatic nitrile anions was conducted, leading to the synthesis of functionalized pyridines bearing a (cyclo)alkyl or saturated heterocyclic substituent. The method demonstrated high chemo- and regioselectivity, as well as excellent scalability, and was applicable to various (hetero)aliphatic nitriles and isomeric halogenated 2- and 4-fluoropyridines. The synthesized products showed utility in additional functional group transformations, providing valuable pyridine-containing building blocks.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Ryo Tsunokawa, Yukiko Karuo, Atsushi Tarui, Kazuyuki Sato, Takaaki Hosoya, Tomohiro Agou, Kentaro Kawai, Masaaki Omote
Summary: Metal-free pyridine arylations have been achieved using O-triflated pyridine N-oxides and N-alkylated indoles. The reactions proceed through reactive intermediates activated by Tf2O treatment, which allow for the selective installation of various indoles at the nitrogen-adjacent positions of pyridine. This protocol offers mild conditions, short reaction times, and ease of handling, making it an environmentally friendly approach to pyridine arylation.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Yan Gao, Qianyi Zhao, Lixin Li, Yan-Na Ma
Summary: The article discusses the synthesis of various N-heterocycles through intramolecular oxidative C-N bond formation as well as the mechanism study, providing new insights for the preparation of N-heterocycles.
Article
Chemistry, Organic
Zhan-Cai Li, Yu Zhang, Bing-Xia Yan, Xiao-Ning Wang, De-Hua Zhai, Qiang Li, Hong-Xing Zheng, Chang-Qiu Zhao
Summary: Biphenyl derived secondary phosphine oxides with 2'-hydroxyl were synthesized and converted to hydroxymethyl phosphine oxides. Chlorination and cyclization led to the formation of a series of P,O-heterocycles. Under LDA treatment, rearrangement occurred to stereoselectively produce hydroxyl substituted cyclic phosphines. The rearrangement was proposed to involve intra-molecular aromatic substitution reactions, resulting in the conversion of P-stereogenic secondary phosphine oxide to a P,C,axial-stereogenic P-cycle.
ORGANIC CHEMISTRY FRONTIERS
(2021)