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)
Review
Biochemistry & Molecular Biology
P. Rahul, Joice Thomas, Wim Dehaen, Jubi John
Summary: This review summarizes several reports on the synthesis of fused 1,2,3-triazole containing scaffolds using a sequential multicomponent reaction-intramolecular azide-alkyne cycloaddition approach. The reactions were carefully designed to incorporate azide and alkyne functionalities in the MCR product, which was then subjected to IAAC. The review is divided into two sections based on the number of components in the multicomponent reaction, and provides a critical discussion and analysis of the advantages and disadvantages of each methodology.
Article
Chemistry, Applied
Byungjun Kim, Sukwoo Lee, Sarah Yunmi Lee
Summary: In this study, a new method was reported to successfully promote the catalytic asymmetric Diels-Alder reactions using a chiral catalyst in conjunction with a chiral isothiourea catalyst or a Bronsted acid, resulting in the synthesis of densely functionalized cyclohexenes with multiple stereocenters.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Cijil Raju, Sooraj Kunnikuruvan, Kana M. Sureshan
Summary: This study presents a new synthetic strategy for the cycloaddition reaction between non-polarized internal alkynes and azides to yield trisubstituted triazoles. By designing a cyclitol-derived monomer with azide and internal alkyne groups, the reactive orientation necessary for topochemical reaction was achieved through the crystal packing of the monomer molecules. Upon heating, the monomer underwent topochemical polymerization to form a trisubstituted-1,2,3-triazole-linked-polycyclitol.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Wanderson C. de Souza, Bianca T. Matsuo, Priscilla M. Matos, Jose Tiago M. Correia, Marilia S. Santos, Burkhard Koenig, Marcio W. Paixao
Summary: N-Alkyl-N-(2-(1-arylvinyl)aryl)cinnamamides can be converted into natural product inspired scaffolds via iridium photocatalyzed intramolecular [2+2] photocycloaddition, allowing the synthesis of a variety of tetrahydrocyclobuta[c]quinolin-3(1H)-ones with high molecular complexity.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Wan-Yu Chen, Wei-Han Lin, Chia-Jou Kuo, Chien-Fu Liang
Summary: N-Sulfonylthioimidate is converted to ketenimine under basic conditions. The reaction with vinyl/aryl azides induces dipolar cycloaddition to form 5-amino-1-vinyl/aryl-1,2,3-triazoles. The method boasts high efficiency, diverse product structures, favorable yields, and applicability to gram-scale operations.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Hongyu Guo, Sheng Zhang, Xiaoqiang Yu, Xiujuan Feng, Yoshinori Yamamoto, Ming Bao
Summary: Palladium and acid cooperative catalysis was proposed as a strategy for the [3 + 2] cycloaddition of acceptor/donor-type diazo compounds with terminal alkynes, resulting in high yields of 2,3,5-trisubstituted furans. This method provides an efficient pathway to prepare furan-containing organosilane and organoboron reagents, while preserving important functional groups during the cycloaddition reaction.
Article
Chemistry, Physical
Juba Ghouilem, Christine Tran, Nicolas Grimblat, Pascal Retailleau, Mouad Alami, Vincent Gandon, Samir Messaoudi
Summary: This study presents a novel Pd-catalyzed reaction for anomeric C-H bond activation, leading to the synthesis of elusive C-(hetero)aryl glycosides with exclusive α-selectivity.
Article
Chemistry, Organic
Lei Zeng, Qian Lei, Weidong Rao, Lizhu Gao
Summary: A catalytic diastereoselective hetero-Diels-Alder reaction was developed for the synthesis of 3,4-dihydropyrans from alpha-haloacroleins and less polarized alkenes. Mechanistic studies revealed that 3,4-dihydropyran was produced through the ring expansion of cyclobutane, which was generated from the ring contraction of an initially formed unstable conformer.
Article
Chemistry, Multidisciplinary
Vignesh Athiyarath, Mithun C. Madhusudhanan, Sooraj Kunnikuruvan, Kana M. Sureshan
Summary: This study demonstrates a novel approach for tuning the secondary structure of a polymer in the solid-state using topochemical synthesis of a pseudoprotein. By utilizing TAAC polymerization, the pseudoprotein undergoes a structural transformation from beta-meander to alpha-helical form when dissolved in methanol. This work opens up new possibilities for controlling the secondary structure of proteins and polymers in the solid-state.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
David Philip Day, Jorge Andres Mora Vargas, Antonio Carlos Bender Burtoloso
Summary: The work presents a new method to access alpha-fluoro-alpha-triazol-1-yl ketones from sulfoxonium ylides via aazido-alpha-fluoro ketone intermediates. This approach allows modification to both reactants and has been demonstrated with 15 examples, yielding between 22% to 75%.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Jun Zheng, Christoph Nopper, Rifhat Bibi, Ali Nikbakht, Felix Bauer, Bernhard Breit
Summary: A dual photoredox/nickel catalyzed method for the regio- and diastereoselective allylation of N-aryl alpha-amino acids is presented. The reaction provides branched homoallylic amines in high yields and high syn-diastereoselectivity under mild and redox-neutral conditions. The broad substrate scope and high functional group tolerance demonstrate the synthetic flexibility of this reaction.
Article
Chemistry, Organic
Yunfeng Du, Yuefei Liu, Hongyu Guo, Rongfang Liu, Rong Zhou
Summary: P(NMe2)(3)-mediated substrate-controlled annulations of azoalkenes with α-dicarbonyl compounds were studied. The azoalkenes can selectively act as either four or five-atom synthons. The reaction with isatins resulted in the formation of spirooxindole-pyrazolines as four-atom synthons, while the reaction with aroylformates led to chemo- and stereoselective formation of pyrazolones as five-atom synthons. The synthetic utilities of the annulations were demonstrated, and a novel TEMPO-mediated decarbonylation reaction was discovered.
Article
Chemistry, Multidisciplinary
Zhi-Xin Zhang, Li-Gao Liu, Yi-Xi Liu, Jian Lin, Xin Lu, Long-Wu Ye, Bo Zhou
Summary: Catalytic enantioselective transformation of alkynes is an important method for synthesizing axially chiral molecules. This study presents an organocatalytic approach for the atroposelective intramolecular (4 + 2) annulation of enals with ynamides. The method allows for the efficient and atom-economical preparation of various axially chiral 7-aryl indolines with good enantioselectivity. Computational studies were conducted to understand the regioselectivity and enantioselectivity, and a chiral phosphine ligand derived from the synthesized molecules showed potential for asymmetric catalysis.
Article
Chemistry, Multidisciplinary
Het Vyas, Ashvin J. Gangani, Aiswarya Mini, Shengjia Lin, Jia-Min Chu, Caitlyn O. Agee, Justin Gabriel, R. Thomas Williamson, Yong Zhang, Abhishek Sharma
Summary: This study reports the development of vinyl cyclopropyl diborons (VCPDBs) as a versatile source of previously unknown homoallylic alpha,alpha-diboryl radicals via thiyl radical catalyzed diboron-directed ring opening. These diboryl stabilized radicals underwent smooth [3+2] cycloaddition with a variety of olefins to provide diboryl cyclopentanes in good to excellent diastereoselectivity. The mild reaction conditions also allowed a one-pot VCP ring-opening, cycloaddition-oxidation sequence to afford disubstituted cyclopentanones. Control experiments and DFT analysis of reaction mechanism support a radical mediated pathway and provide a rationale for the observed diastereoselectivity. To the authors' knowledge, these are the first examples of the use of geminal diboryl group as an activator of VCP ring opening and cycloaddition reaction of alpha-boryl radicals.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
