Article
Chemistry, Multidisciplinary
Peter Wonneberger, Nils Koenig, Menyhart B. Sarosi, Evamarie Hey-Hawkins
Summary: Reduction of 1-phospha-2-azanorbornene derivative leads to formation of a novel compound 1-phosphabicyclo[3.2.1]octa-2,5-diene and an unusual 2H-phosphole dimer. Additionally, 3H-phospholes were found to potentially act as dienophile in the dimerisation reaction under elevated temperatures, contrary to previous assumptions of their synthetic irrelevance.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Applied
Tsai-Hui Lung, Yi-Ru Chen, Chen-Ling Chang, Wey-Chyng Jeng, Pei-Shan Wu, Sandip Sambhaji Vagh, Gangababu Marri, Yi-Fang Lin, Wenwei Lin
Summary: A catalyst-controlled diversity-oriented synthesis of spirohydroquinoline-indandiones and 3-methylenehydroquinoline-indandiones was reported using ortho-sulfonamidophenyl-substituted para-quinone methides and allylidene-indandiones. Organobases such as DMAP or TMG were utilized to selectively control the reaction pathway, resulting in products with yields of 40-99% and excellent diastereoselectivities. Mechanistic studies revealed that spirohydroquinoline-indandione was the kinetic product, which underwent an unusual base-initiated 1,3-nitrogen rearrangement process to afford 3-methylenehydroquinoline-indandione in the presence of TMG.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Applied
Tianlong Zeng, Jingyang Kong, Hongkai Wang, Lingyan Liu, Weixing Chang, Jing Li
Summary: Substituent-controlled divergent cascade cycloaddition reactions of chalcones and arylalkynols in the presence of PtI2 were reported, yielding either spiroketals or oxa-bridged fused heterocycles depending on the substituent on the chalcone. Control experiments elucidated the high chemoselectivity, providing a method for the synthesis of a diverse array of structurally complex oxygen-containing heterocycles.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Petr Henke, Cecilie Rindom, Um Kanta Aryal, Malte Frydenlund Jespersen, Line Brolos, Mads Manso, Vida Turkovic, Morten Madsen, Kurt V. Mikkelsen, Peter R. Ogilby, Mogens Brondsted Nielsen
Summary: One key challenge in the development of viable organic photovoltaic devices is to design component molecules that do not degrade during combined exposure to oxygen and light. Novel redox-active chromophores that combine these two properties were designed and tested in non-fullerene acceptor based organic photovoltaic proof-of-principle devices, showing enhanced device stability.
Article
Chemistry, Multidisciplinary
Lin-Xuan Wang, Bin Qiu, Xiao-De An, Pei-Zhen Dong, Rui-Bin Liu, Jian Xiao
Summary: The unprecedented organocatalytic cascade aldimine condensation/[1,6]-hydride transfer/Mannich-type cyclization of indole-2-carbaldehydes with o-aminoanilines was successfully developed to assemble polycyclic indole-2,3-fused diazocanes in one step. This novel methodology is highly efficient, metal-free, redox-neutral, and capable of operating at room temperature, providing a new approach for utilizing hydride transfer chemistry in constructing medium-sized ring structures.
Article
Chemistry, Organic
Evgeny B. Ulyankin, Anastasia S. Kostyuchenko, Sergey A. Chernenko, Mikhail O. Bystrushkin, Anna L. Samsonenko, Anton L. Shatsauskas, Alexander S. Fisyuk
Summary: A new approach based on iodine-promoted photocyclization was developed for the synthesis of fused benzothiophene derivatives, providing an efficient method compared to traditional oxidative coupling and palladium-catalyzed intramolecular arylation. This method allows for the synthesis of a variety of functionally substituted fused heterocycles containing pyridine and carbazole moieties.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Applied
Sandor Balazs Kiraly, Laszlo Toth, Tibor Kovacs, Attila Benyei, Erika Lisztes, Balazs Istvan Toth, Tamas Biro, Attila Kiss-Szikszai, Katalin E. E. Kover, Attila Mandi, Tibor Kurtan
Summary: Four series of chiral condensed heterocycles, representing four novel skeletons and exhibiting antiproliferative activity, were synthesized through Domino Knoevenagel-cyclization reactions of 2H-chromene and chroman derivatives containing o-formylaryl amine or ether side-chain. The cyclization occurred through four different mechanisms: a concerted intramolecular hetero Diels-Alder reaction (IMHDA), a stepwise polar [2+2] cycloaddition, a [1,5]-hydride shift-6-endo cyclization, or a multi-step nitro hetero Diels-Alder-ring-opening-Cadogan-type cyclization sequence. The latter reaction provided a novel route to hydroxyindoles through an inverse Cadogan-type cyclization, where the nitro group is deoxygenated by a nitro IMHDA-ring-opening sequence. The cyclization mechanisms and stereoselectivity were studied using DFT calculations, which allowed for proposing a mechanism for the multi-step cyclization to hydroxyindoles and explaining the observed diastereoselectivity.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Linpeng Liu, Yanyu Jian, Weigao Hu, Shaohu Zhao, Zhang-Jie Shi, Nicklas Selander, Taigang Zhou
Summary: A method for radical cyclization and ring-opening of oxime esters with diselenides has been developed. Both Ni(0) and Fe(ii) catalysts can be used for the selenylation of olefin-containing and cyclic oxime ester derivatives. Using this method, a variety of functionalized pyrrolines and alkyl nitriles can be synthesized in good yields. Additionally, a mechanism involving iminyl radical and carbon-centered radical intermediates has been proposed.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Organic
Maruti B. Yadav, Sandip S. Vagh, Yeon Tae Jeong
Summary: An efficient method for constructing spiro[indoline-pyran] and fused (epoxyetheno)indeno[1,2-b]furan compounds has been developed from 1-cyanoketones and 1,2-diketones through Knoevenagel and Michael adduct reactions. This synthesis allows for the preparation of heterocyclic compounds with one or more tetra-substituted carbon centers and sequential hexa- and penta-cyclic core under mild conditions, showing excellent chemo and regioselectivity. Additionally, the synthesis was demonstrated on a gram scale.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Changtong Zhu, Zhenbo Yuan, Zhiwei Deng, Dejing Yin, Yan Zhang, Jingwen Zhou, Yijian Rao
Summary: By engineering the enzyme GluER and combining it with photoenzymatic synthesis, the efficient asymmetric synthesis of oxygen-containing benzo-fused heterocycles has been achieved, providing a green approach for the synthesis of important chiral motifs in pharmaceuticals.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Elisa Brambilla, Silvia Meraviglia, Edoardo Moneta, Donatella Nava, Silvia Rizzato, Giorgio Abbiati, Valentina Pirovano
Summary: A photoredox-promoted approach for the synthesis of [1,4]diazepino[1,7-a]indol-6(7H)-ones starting from N-indolyl phenylacrylamides and aroyl chlorides as radical source is reported. This method involves a cascade radical addition on C-C double bond followed by intramolecular cyclization at indole C2-position, resulting in the formation of two diastereomeric indole-fused 1,4-diazepinones characterized by a N-C(aryl) axial chirality, with yields ranging from 51% to 99%.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Hai-xuan Liu, Fei Ji, Yu Chen, Ya Gao, Jun-ke Wang, Ming-zhi Zhang, Fang Liu, Qiang Sha
Summary: This study reports a divergent synthesis of a variety of 2 alpha- and 5 alpha-substituted furan derivatives from 2-hydroxy-1,4-diones, achieved through selective reactions using different substrates and catalysts. The products showed moderate antifungal activity against Rhizoctorzia solani and Botrytis cinerea.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Organic
Qingsong Deng, Aimin Yu, Lei Zhang, Xiangtai Meng
Summary: A stereospecific three-component domino reaction was revealed under catalyst-free conditions, leading to the synthesis of a wide range of benzothiophene-fused polycycles and eight-membered N-heterocycles. The control over product formation was achieved by regulating the stereoconfiguration of cyclohexane-1,2-diamines. The detailed mechanism and origin of the chemoselectivity were explored using density functional calculations, revealing the influence of intramolecular attractions and steric effects on the observed chemoselectivity.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Yufei Song, Zhaolin Quan, Zhengkai Chen, Xiao-Feng Wu
Summary: A facile and straightforward method for the synthesis of fused quinoxalinones has been achieved via palladium-catalyzed cascade carbonylative cyclization. The transformation involves cascade carbonylation, acyl azide formation, Curtius rearrangement, and intramolecular cyclization. The obtained heterocycle products can be easily converted into structurally diverse valuable compounds, demonstrating the synthetic utility of the developed protocol.
Article
Chemistry, Organic
Yanfeng Gao, Hui Wang, Xiaoquan Chen, Yiyang Qiao, Zhiwei Miao
Summary: We present a highly efficient and diastereoselective gold and palladium sequential relay catalysis system for the synthesis of furan-fused eight-membered heterocycles. By utilizing a one-pot procedure, readily available enynamides undergo cyclization to generate azadienes in situ, which then engage in diastereoselective formal[4 + 4] cycloadditions with gamma-methylene-delta-valerolactones. This method enables the rapid and efficient construction of a range of furan-fused azacyclooctanes with diverse substituents in good yields (63-97%) and a high level of diastereoselectivity (7:1 → 20:1 dr).
JOURNAL OF ORGANIC CHEMISTRY
(2023)
