Article
Chemistry, Organic
Hongjun Jeon, Sang Won Choi, Soojun Park, Seokwoo Lee, Sanghee Kim
Summary: In this study, a facile method for generating O-acyloxocarbenium ions (AOIs) from ester and acetal groups was presented, resulting in a unique bridged bicyclic system. The proposed mechanism for the reaction was based on experimental and computational studies, revealing the formation pathway through an epoxonium-like transition state.
Article
Chemistry, Multidisciplinary
Man-Bo Li, Jie Yang, Ying Yang, Guo-Yong Xu, Gen Luo, Jianping Yang, Jan-E. Backvall
Summary: A solid amino-supported palladium catalyst is used for the diastereoselective construction of alkyne-substituted cyclopentenol compounds in an oxidative domino reaction. This heterogeneous catalyst shows high efficiency, excellent chemoselectivity, and good recyclability, with the chemoselectivity of the domino reactions easily controlled by switching the solvent and catalyst. Asymmetric syntheses and an oxidative carbocyclization-borylation reaction have also been developed based on this heterogeneous palladium catalyst.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Hiroyuki Mutoh, Shu Nakamura, Koichi Hagiwara, Masayuki Inoue
Summary: Limonoids 1 and 2 share a 6/6/6/5-membered ABCD ring system and a six-membered oxacycle, but differ in their C9-stereochemistries. A novel radical-based strategy was developed to construct the pentacyclic skeletons of 1 and 2, by coupling oxacycle-fused A-ring and enyne fragments to produce radical precursors 4a-4c with different C7-oxygen functionalities, which then participated in a radical cascade reaction to cyclize the C9-diastereomeric BCD rings.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Yujie Dong, Jun Liu, Xing Gao, Ting Pan, Biming Mao, Songcheng Yu, Yongjun Wu, Cheng Zhang, Hongchao Guo
Summary: A palladium-catalyzed cascade cyclization was developed for the synthesis of biologically active tetracyclic dihydrocyclopentaindenofuranone derivatives. The reaction exhibited moderate to high yields and excellent diastereoselectivities, with the allene moiety fully fused into the cyclopentene ring.
CHINESE CHEMICAL LETTERS
(2023)
Article
Chemistry, Organic
Nilay Kanova, Buse Aysen Dundar, Yilmaz Kelgokmen, Metin Zora
Summary: A one pot two step protocol has been developed for the synthesis of 2-acetyl-1H-pyrroles from N-propargylic beta-enaminones. The method is general, providing a diverse range of products with good to high yields and tolerating various functional groups. This operationally easy method offers a rapid access to functionalized 2-acetyl-1H-pyrroles with potential pharmacological interest.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Satheeshvarma Vanaparthi, Mamta, Jyothi Yadav, Amol Prakash Pawar, Eldhose Iype, Sravendra Rana, Indresh Kumar
Summary: A two-pot synthesis of 5-aza-indoles has been achieved using aqueous succinaldehyde and N-aryl propargylic-imines, involving a metal-free annulation and Ag-catalyzed cyclization. The resulting 5-aza-indoles exhibit interesting photophysical activities, and the feasibility of this economically viable gram-scale synthesis has been demonstrated.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Indranil Halder, Akshay M. Nair, Samyadev Giri, Chandra M. R. Volla
Summary: Here, we report the use of PhTeTePh as an uncommon reducing agent in the reductive hydrazo-sulfonylative difunctionalization cascade of alkynyl cyclohexadienones. Diphenyl ditelluride, a commercially available solid with good solubility in most organic solvents, was employed for the first time as a reducing agent. The protocol allowed for the synthesis of various difunctionalized dihydrochromenones and dihydrobenzofuranones in good yields under mild conditions. The reactions were scalable, and mechanistic studies were conducted. Additionally, photophysical studies revealed significant absorption (400-450 nm) and emission (520-570 nm) of the products in the visible region.
Article
Chemistry, Multidisciplinary
Heinrich F. von Koeller, Finn J. Geffers, Pedram Kalvani, Adrian Foraita, Patrick-Eric J. Loss, Burkhard Butschke, Peter G. Jones, Daniel B. Werz
Summary: A new route to dyes of the BODIPY family is presented in this study. A N-Boc-protected dipyrromethene scaffold was first constructed via an aminopalladation cascade, followed by deprotection of the pyrrole moiety and insertion of the BF2 unit. Depending on the terminating reaction, BODIPYs with either aryl or alkynyl moieties can be obtained.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Bowen Jiang, Xiangyu Yan, Yong Xu, Natalya Likhanova, Heriberto Diaz Velazquez, Yanyan Gong, Ye Yuan, Francis Verpoort
Summary: This article provides a systematic review of the tandem reactions of carboxylative cycloaddition of CO2 into propargylic alcohols with hydration, amination, alcoholysis, and isomerization to synthesize various organic compounds.
Article
Chemistry, Organic
Chao Pei, Zhen Yang, Rene M. Koenigs
Summary: The photochemistry of palladium catalysis is an efficient strategy for cross coupling and multifunctionalization reaction of olefins via alkyl radicals. In this study, it has been demonstrated that isonitriles can act as radical acceptors and participate in a further radical cascade cyclization to produce phenanthridine derivatives. Moreover, this photocatalytic process has also been extended to cascade methylation reaction in one-pot using TMSCH2I as the radical precursor. Experimental and computational studies suggest that an intramolecular single electron transfer process is involved in the generation of alkyl radicals in this transformation.
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, Organic
Indranil Halder, Akshay M. Nair, Samyadev Giri, Chandra M. R. Volla
Summary: Here, we describe a novel reductive hydrazo-sulfonylative difunctionalization cascade of alkynyl cyclohexadienones using PhTeTePh as an uncommon reducing agent. Diphenyl ditelluride, a commercially available solid with good solubility in organic solvents, is reported for the first time as a reducing agent. The protocol enables the synthesis of diverse difunctionalized dihydrochromenones and dihydrobenzofuranones in good yields under mild conditions. Mechanistic studies were conducted to investigate the reaction mechanism, and photophysical studies of the products revealed significant absorption (400-450 nm) and emission (520-570 nm) in the visible region.
Article
Chemistry, Multidisciplinary
Wang Yao, Chuan-Jun Lu, Li-Wen Zhan, Yi Wu, Jia Feng, Ren-Rong Liu
Summary: In this study, a palladium-catalyzed enantioselective C-H activation method for pyrroles was reported, which successfully synthesized structurally diverse indole-pyrrole atropisomers with a chiral N-N axis, showing high yields and enantioselectivities. Furthermore, the kinetic resolution of trisubstituted N-N heterobiaryls with more sterically demanding substituents was also achieved. This versatile method enables the rapid and selective functionalization of pyrroles, facilitating the synthesis of valuable and complex N-N atropisomers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Editorial Material
Chemistry, Multidisciplinary
Shiyao Liu, Yoshiaki Tanabe, Shogo Kuriyama, Ken Sakata, Yoshiaki Nishibayashi
Summary: The cover of this issue features the research on the propargylic substitution reaction of propargylic alcohol with an N-monosubstituted hydrazone, where the nucleophilicity of the hydrazone is controlled by the choice of catalytic system. The full article can be accessed at 10.1002/chem.202103287.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Shiyao Liu, Yoshiaki Tanabe, Shogo Kuriyama, Ken Sakata, Yoshiaki Nishibayashi
Summary: In this study, propargylic substitution reactions using ruthenium and copper catalysis with N-monosubstituted hydrazones as ambident nucleophiles were investigated. It was found that N-monosubstituted hydrazones exhibited different reactivities depending on the catalytic system, resulting in either propargylic alkylated or aminated products. DFT calculations were used to study the reaction pathways and further transformation of the products yielded multisubstituted pyrazoles in good to high yields.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Organic
Geeta Devi Yadav, Pooja Chaudhary, Balaram Pani, Surendra Singh
Summary: Chiral transition metal complexes with privileged ligands are efficient catalysts for various asymmetric organic transformations. Transition metal complexes of C1-symmetric pyrrolidine-based ligands have been widely used in asymmetric organic reactions. However, a comprehensive review article on the transition metal complexes of chiral C1-symmetric pyrrolidine-based ligands derived from (L)-proline has not been published.
TETRAHEDRON LETTERS
(2024)
