Article
Chemistry, Organic
Jacob C. Hood, Yannick Tshikaya, Aaren R. Manz, Marcus C. LaPorte, Douglas A. Klumpp
Summary: In this study, a series of conjugate addition reactions were successfully performed using vinyl-substituted N-heterocycles in acid-catalyzed conversions, resulting in the formation of pyridyl and related heterocyclic products. The nucleophiles used in these reactions include 1,3-dicarbonyl compounds, cyano esters, cyano sulfone, and malonylnitrile, while the Michael accepting groups include vinyl-substituted pyridines, quinoline, and pyrazine. Double conjugate addition reactions were also achieved using 2,6-divinylpyridine and related systems.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Jacob C. Hood, Maksim V. Anokhin, Douglas A. Klumpp
Summary: N-Heterocyclic alcohols have been proven to be excellent substrates for superacid-promoted Friedel-Crafts reactions. The ionization of N-heterocyclic alcohols produces reactive, dicationic intermediates, leading to good to excellent yields of arylation products.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Chao Hu, Cuong Vo, Rohan R. Merchant, Si-Jie Chen, Jonathan M. E. Hughes, Byron K. Peters, Tian Qin
Summary: Heterocycles play a crucial role in modern medical chemistry and drug development. In this study, a simple and efficient method was developed to selectively synthesize hydrosilylated and reduced N-heterocycles from abundant aromatic building blocks. This approach has the potential to facilitate the synthesis of novel medicinally relevant scaffolds.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Pannan Miao, Ruining Li, Xianfeng Lin, Liangming Rao, Zhankui Sun
Summary: Cascade reactions are efficient and environmentally friendly methods for constructing multiple carbon-carbon bonds in one step. This method involves a relay olefination and radical addition process induced by visible light, offering mild conditions, robustness, and excellent functionality compatibility. The synthetic utility of this approach is demonstrated by a two-step synthesis of indolizidine 209D.
Review
Biochemistry & Molecular Biology
Gheorghe Ilia, Vasile Simulescu, Nicoleta Plesu, Vlad Chiriac, Petru Merghes
Summary: Carbonyl olefinations are important organic syntheses for forming C=C bonds, often with high yields and excellent stereoselectivity. The Wittig reaction is a well-known carbonyl olefination method, involving the reaction between an aldehyde or ketone and a Wittig reagent. The use of ultrasound in these reactions, including modified Wittig syntheses, has been studied for green synthesis and improved yields and reaction times.
Article
Chemistry, Multidisciplinary
Grant J. Sherborne, Paul Kemmitt, Callum Prentice, Eli Zysman-Colman, Andrew D. Smith, Charlene Fallan
Summary: This study developed a light-mediated cyclisation method for the selective synthesis of tetrahydroquinolines or quinoline derivatives. The method is efficient, atom economical, and tolerant to functional groups, including azaarene-bearing substrates.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Kunlayanee Punjajom, Sureeporn Ruengsangtongkul, Jumreang Tummatorn, Praneet Paiboonsombat, Somsak Ruchirawat, Charnsak Thongsornkleeb
Summary: A general protocol for oxidative annulation was developed to prepare 2-methyl-3,4-diacylquinolines directly from 2-alkynylanilines and 1,3-ketoesters. The reactions were mediated by Mn(OAc)3 in acetic acid at room temperature, leading to the desired quinoline products in one-pot in low to good overall yields on a wide range of substrates. The current method is convenient, conducted under mild conditions, and has short reaction times.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Daniel Moser, Kalipada Jana, Christof Sparr
Summary: In this study, the feasibility of atroposelective P-III/P-V=O redox organocatalysis by the Staudinger-aza-Wittig reaction is described. The formation of isoquinoline heterocycles allows for the synthesis of a wide range of valuable atropisomers with high enantioselectivities. The reaction is catalyzed by a chiral phosphine catalyst, with stereocontrol achieved through a silane reductant and Bronsted acid co-catalysis. The products can be easily transformed into N-oxides, naphthol, and triaryl phosphine variants, providing access to diverse aromatic heterocycles with precise control over their configuration.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Cai-Yan Zhang, Ke Cao, Han-Bo Yang, Li-Fang Ding, Junxiao Yang
Summary: The Cu(OTf)(2)/NBS-mediated tandem reaction of 1-cinnamyl alcohol-o-carboranes for the synthesis of C-alkenyl-o-carboranes has been developed. Mechanism studies revealed that the ring opening of oxetane with electron-rich arenes as nucleophiles, promoted by Cu(OTf)(2), was the key step for the transformation. This work provides an alternative strategy for the synthesis of C-alkenyl-o-carboranes, which has important implications for diversifying o-carborane derivatives.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Lixin Niu, Yun He, Jin Xi, Tao Wang, Yong Liang, Zunting Zhang
Summary: The method utilizes UV irradiation to achieve the synthesis of 6-phenylbenzo[h]quinolines without the need for transition metal catalyst and oxidant, offering high atom efficiency and mild reaction conditions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Qiang Tang, Meng Yuan, Jiahui Duan, Keke Xu, Ruxue Li, Mengqing Xie, Shuwen Kong, Xinwei He, Yongjia Shang
Summary: A concise and efficient synthetic method for alkynyl quinolines has been established through TfOH-promoted cascade reactions, providing a variety of products with good to excellent yields. This transition-metal-free process is tolerant to halogen groups, circumventing the inherent shortcomings of existing Sonogashira coupling reactions for halogenated quinolines.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Loana I. Monzon, Nicole C. M. Rocha, Gabriela T. Quadros, Pamela P. P. Nunes, Roberta Cargnelutti, Raquel G. Jacob, Eder J. Lenardao, Gelson Perin, Daniela Hartwig
Summary: A general methodology for synthesizing valuable 4-(phenylchalcogenyl)tetrazolo[1,5-a]quinolines was developed by reacting 2-azidobenzaldehyde with phenylchalcogenylacetonitriles using potassium carbonate as a catalyst. The method tolerated a variety of functional groups and yielded twelve different 4-(phenylchalcogenyl)tetrazolo[1,5-a]quinolines selectively. The structure of the synthesized 4-(phenylselenyl)tetrazolo[1,5-a]quinoline was confirmed by X-ray analysis.
Review
Chemistry, Physical
Tong-De Tan, Ze-Shu Wang, Peng-Cheng Qian, Long-Wu Ye
Summary: Ynamides, as electron-rich heteroatom-substituted alkynes, have proven to be versatile reagents for organic synthesis and have received extensive attention. Radical reactions of ynamides, categorized by radical attack at the alpha-position and beta-position, are reviewed in this article to highlight reaction selectivity, scope, mechanism, and applicability. The aim is to provide a comprehensive summarization of these advances to guide the further development of ynamide chemistry.
Article
Chemistry, Physical
Shivangi Gupta, Ankur Maji, Dibyajyoti Panja, Mita Halder, Sabuj Kundu
Summary: Efficient synthesis of quinolines, pyridines, and pyrroles via alcohol dehydrogenative coupling strategy using copper oxide nanoparticles as catalyst is reported. Various functionalized quinolines, pyridines, and pyrroles were efficiently synthesized from different amino alcohols and a diverse range of ketones. Control experiments were conducted to elucidate the mechanism. The catalyst showed no significant loss in catalytic activity after being recycled up to 6 runs.
JOURNAL OF CATALYSIS
(2022)
Article
Biochemistry & Molecular Biology
Alexander Aksenov, Nikita K. Kirilov, Nicolai A. Aksenov, Dmitrii A. Aksenov, Elena A. Sorokina, Carolyn Lower, Michael Rubin
Summary: Nitroalkanes activated with polyphosphoric acid can act as efficient electrophiles in reactions with amines and hydrazines, leading to various cascade transformations towards heterocyclic systems. This strategy involves simultaneous or sequential annulation of two different heterocyclic cores, resulting in [1,2,4]triazolo[4,3-a]quinolines with 1,3,4-oxadiazole substituents.
