Article
Chemistry, Organic
Jing Liu, Yi Zhou, Jiaqi Zhu, Zhi-Xiang Yu
Summary: The report describes a synthetic strategy for molecules with linear tricyclic 5/5/5 and 6/5/5 skeletons using a [5 + 2 + 1]/ene approach. The strategy involves a Rh-catalyzed [5 + 2 + 1] reaction followed by an InCl3-catalyzed ene reaction to transform the intermediates into the final target molecules, offering an efficient and feasible synthetic route.
Article
Chemistry, Multidisciplinary
Yueyao Chen, Jesse Ling, Angus B. Keto, Yun He, Kam-Hung Low, Elizabeth H. Krenske, Pauline Chiu
Summary: Epoxy and aziridinyl enolsilanes can react as oxyallylic cation equivalents in highly selective and stereoselective intramolecular (3+2) cycloadditions. Computational studies suggest that the stepwise reaction involves the conformational flexibility of the intermediate, which determines the formation of (3+2) cycloadducts. This method can be used for the synthesis of densely functionalized trans-hydrindane scaffolds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Anh Le, Daesung Lee
Summary: This study explores the substituent-dependent reactivity and selectivity in intramolecular reactions of arynes tethered with different allene isomers. It is found that the presence of 1,3-disubstituted allene favors an Alder-ene reaction over a [2 + 2] cycloaddition, while a 1,1-disubstituted allene prefers the [2 + 2] cycloaddition. Additionally, a 1,1,3-trisubstituted allene-tethered aryne shows preference for an Alder-ene reaction over a [2 + 2] cycloaddition.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Tsukasa Tawatari, Ritsuki Kato, Riku Kudo, Kiyosei Takasu, Hiroshi Takikawa
Summary: In this study, we report on the intramolecular (3+2) cycloaddition reactions between ynamides and benzyne. These reactions involve the formation of two bonds and are facilitated by using benzyne precursors containing a chlorosilyl group. The intermediate indolium ylide in these reactions exhibits both nucleophilic and electrophilic properties at its C2 atom.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Jing Liu, Yi Zhou, Zhi-Xiang Yu
Summary: A six-step total synthesis of isohirsut-4-ene with a 5/5/5 tricyclic core has been achieved using a three-step strategy that involves a Rh(I)-catalyzed [5+2+1] cycloaddition, a Corey-Chaykovsky reaction, and a transannular epoxide-alkene cyclization. This strategy was further applied to synthesize more tricyclic analogues with one or two bridgehead quaternary centers.
Article
Chemistry, Organic
Li Jing, Zhong-Jun Li, Er-Qing Li
Summary: We have developed a new 1,3-bis-electrophilic motif and applied it in palladium-catalyzed (3 + 2) annulations. This method offers a straightforward approach to constructing functionalized pyrrolidines with good yields. Importantly, the configuration (Z/E) of the 1,3-bis-electrophilic motif does not affect the yield and chemoselectivity of the reaction. Furthermore, preliminary asymmetric investigations using Pd(0)/thiourea synergistic catalysis resulted in moderate enantioselectivity.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Yong Hu, Xiao-Jun Wang, Wen-Shuai Dong, Yu-Fan Bi, Zu-Jia Lu, Wen-Li Cao, Jian-Guo Zhang, Qi Zhang, Dong Chen
Summary: A new method using DBFO and sodium azide for the synthesis of tetrazole-based energetic materials was reported, and the synthesized energetic salts were fully characterized using various analytical techniques. The heat of formation and detonation parameters of nitrogen-rich salts were calculated, confirming the effectiveness of this reaction. This method not only offers a new synthetic route for tetrazoles, but also reveals a new reactivity of DBFO.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
Hai-Tao Zhu, Chun-Miao Liang, Ting-Yan Li, Lin-Yan Li, Rui-Ling Zhang, Jun-Na Wang, Rui-Qing Qi, Jia-Min Zhang, Ruo-Han Yang, Yin-Qi Yang, An-Xi Zhou, Xiaojie Jin, Ni-Ni Zhou
Summary: A one-pot step-economic tandem process involving (5 + 2)-cycloaddition and Nazarov cyclization reactions has been developed for the synthesis of indanone-fused benzo[cd]azulenes. The reaction is highly regio- and stereoselective and enabled by dual silver and Bronsted acid catalysis, providing a new avenue for the construction of important bicyclo[5.3.0]decane skeletons.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Timur O. Zanakhov, Ekaterina E. Galenko, Mikhail S. Novikov, Alexander F. Khlebnikov
Summary: A diazo strategy for intramolecular azirine ring expansion was developed. Azirinyl-substituted diazodicarbonyl compounds, prepared from diazoacetylazirines, were efficiently converted to 2-hydroxy-3-oxo-2,3-dihydro-1H-pyrrole-2-carboxylates under Rh catalysis and in the presence of water. The formation of only pyrrolinone derivatives and the absence of O-H insertion products of Rh carbene into water can be attributed to the low Gibbs free energy of the transition state for the concerted opening of the azirine ring and recyclization to pyrrolone in intermediate Rh complexes.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Andreas B. zur Bonsen, Ricardo A. Peralta, Thomas Fallon, David M. Huang, Jonathan H. George
Summary: This study proposes a unified biosynthetic pathway for the synthesis of complex flavonoid analogues. Additionally, it discovers uncatalyzed, intramolecular carbonyl-ene reactions that occur spontaneously at room temperature. Furthermore, an anionic cascade reaction is developed to access four distinct natural product scaffolds from a common intermediate.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Applied
Takeshi Yasui, Yuya Nakazato, Koutarou Kurisaki, Yoshihiko Yamamoto
Summary: In this study, a Rh-catalyzed asymmetric [2+2+2] cycloaddition reaction was reported, resulting in the synthesis of enantio-enriched tricyclic cyclohexadienes with a quaternary bridgehead carbon. It was found that the Rh-Phanephos complex was the most suitable catalyst, while Rh-biaryl bisphosphine catalysts were not applicable.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Zhi Zhao, Xing-Xing Yang, Guang-Yao Ran, Qin Ouyang, Wei Du, Ying-Chun Chen
Summary: This study presents palladium-catalyzed regiodivergent asymmetric annulations of vinyl indoloxazolidones, which can act as 1,5-carbodipoles or 1,3-carbodipoles by tuning the chiral ligands and conditions, in the assemblies with sulfamate-derived cyclic imines and even activated alkenes. A diversity of polycyclic products are generally constructed with high regio- and enantioselectivity.
Article
Chemistry, Multidisciplinary
Durgesh Gurukkala Valapil, Priyanka Mishra, Kalyani Jungare, Nagula Shankaraiah
Summary: A facile [3+3] annulation method for the construction of fused a-carboline or indolo[2,3-c]isoquinoline frameworks from easily synthesizable N,N'-cyclic azomethine ylides and 3-diazoindolin-2-imines using a Ru(II) catalyst is reported. This strategy was found to be efficient and effective for the syntheses of a variety of fused polycyclic molecules with a wide substrate scope, mild reaction conditions, and good to excellent yields. In addition, the mechanistic pathway of this transformation has been investigated by performing various control experiments with ESI-MS analyses.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Organic
Melanie A. Drew, Andrew J. Tague, Christopher Richardson, Stephen G. Pyne, Christopher J. T. Hyland
Summary: A two-step Pd-catalyzed (3 + 2) cycloaddition/HNO2 elimination reaction sequence has been developed to efficiently produce novel cyclic 1,3-dien-5-yne systems with high atom efficiency. The research allows for the selective isolation of a single diastereoisomer of the cycloadduct, demonstrating the potential for practical applications in organic synthesis.
Article
Chemistry, Organic
Jiang-Xi Yu, Li-Jun Wu, Zhi-Qiang Wang, Zhi-Feng Xu, Jin-Heng Li
Summary: A new method for the synthesis of 3-ethynyl-1-methylene-1,2-dihydronaphthalenes is described, involving copper-promoted palladium-catalyzed intermolecular alkynylative [5 + 1] carboannulation of 1-arylphenyl-prop-2-yn-1-yl acetates. The method shows excellent selectivity control, broad substrate scope, and good tolerance of functional groups by using two terminal alkyne molecules as alkynylation reagent and a one-carbon unit.
ORGANIC CHEMISTRY FRONTIERS
(2022)
