Article
Chemistry, Organic
Matthew S. McVeigh, Neil K. Garg
Summary: The study investigates the potential existence of a monoradical pathway in strained cyclic allene reactivity, which was confirmed to be viable.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Applied
Pei-Pei Xu, Su-Ge Xin, Xue Li, Cui Liang, Dong-Liang Mo
Summary: We developed a copper(II)-catalyzed [3+2] cycloaddition reaction between N-aryl-alpha,beta-unsaturated nitrones and disubstituted allenoates to prepare a variety of [1,3]oxazino[3,2-a]indolines and dihydropyrido[1,2-a]indolines in moderate to excellent yields. Mechanistic studies revealed the kinetic preference for [1,3]oxazino[3,2-a]indoline and the thermodynamic preference for dihydropyrido[1,2-a]indoline. The reaction can be easily scaled up and chiral dihydropyrido[1,2-a]indoline can be obtained using a chiral auxiliary. The method demonstrates broad substrate scope, good functional group tolerance, and high diastereoselectivity, making it highly significant.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Baolei Wang, Marius-Georgian Constantin, Simarpreet Singh, Yuqiao Zhou, Rebecca L. Davis, F. G. West
Summary: Keto-substituted 1,2-cyclohexadienes were generated through base-mediated elimination and dimerized via an unprecedented formal hetero-Diels-Alder process, followed by hydration. These highly reactive cyclic allene intermediates showed high regio- and diastereoselectivity in Diels-Alder reactions, and could also react with enamine dienophiles in a hetero-Diels-Alder process.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Rudolfs Belaunieks, Mikus Purins, Rebeka Anna Lipina, Anatoly Mishnev, Maris Turks
Summary: This study focuses on the activation of terminal alkynes with a silyl group and the synthesis of stereochemically defined allyl ethers and esters through 1,2-silyl group migration and interception reactions with external nucleophiles. The obtained products can serve as building blocks for further functionalization reactions.
Article
Chemistry, Multidisciplinary
Christian L. L. Jankovic, Kyle C. C. McIntosh, Verner A. A. Lofstrand, F. G. West
Summary: Mild fluoride-mediated desilylative conditions generate 1,2-cyclohexadienes, which undergo efficient intramolecular [2+2] trapping to form tricyclic alkylidene cyclobutanes with complete diastereoselectivity for the cis-fused products. These cyclohexadienes can be trapped by pendent styrenes or electron-deficient olefins, and 14 substrates have been disclosed. The reactions achieve yields up to 91% at ambient temperature using only cesium fluoride and the necessary precursors are easily accessible from substituted 2-bromocyclohexenones.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Jiaxin Liu, Yin Wei, Min Shi
Summary: A new method for the direct single-electron oxidation of methylenecyclopropanes (MCPs) was reported, leading to the rapid construction of 4-aryl-1,2-dihydronaphthalene derivatives through merging visible light photoredox catalysis and cobalt catalysis. In MeCN with Et3N·3HF, fluorinated derivatives were obtained in moderate yields, while in MeCN/HFIP, good yields were achieved through a MHAT process.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
Alexander A. Lukoyanov, Andrey A. Tabolin, Yulia Nelyubina, Sema L. Ioffe, Alexey Yu. Sukhorukov
Summary: It has been discovered that six-membered cyclic nitronates can react with aryne to form a tricyclic nitroso acetal. This reaction involves the selective cleavage of the N-O bond of the isoxazoline ring, leading to the synthesis of compounds with potential synthetic value.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Yi-Lin Wang, Peng-Xiang Liu, Huan-Huan Zhang, Peng-Fei Xu, Yong-Chun Luo
Summary: A new two-step, one-pot synthesis method for benzo[f][1,2]thiazepine 1,1-dioxides has been developed, involving a visible-light mediated aza Paterno-Buchi reaction and a Lewis acid catalyzed ring-expansion reaction. The mechanism of the aza Paterno-Buchi reaction was also investigated in this study.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Soumen Biswas, Luca De Angelis, Gildardo Rivera, Hadi Arman, Michael P. Doyle
Summary: 1,2,3-Triazine 1-oxides are highly effective substrates for inverse electron demand Diels-Alder reactions. These stable heterocyclic compounds, formed from vinyldiazoacetates via reaction with tert-butyl nitrite, undergo clean nucleophilic addition reactions with amidines to form pyrimidines, with beta-ketocarbonyl compounds and related nitrile derivatives to form polysubstituted pyridines, and with 3/5-aminopyrazoles to form pyrazolo[1,5-a]pyrimidines, in high yields. These reactions, catalyzed by bases, are rapid at room temperature and allow for a range of structural modifications.
Article
Chemistry, Organic
Jia-Hao Zeng, Ding-Chang Li, Sheng Zhang, Zhuang-Ping Zhan
Summary: This study presents a chemodivergent protocol for the synthesis of branched and linear allylic sulfones bearing a conjugated (Z,E)-1,3-diene scaffold by Pd-catalyzed coupling of allenes with sulfinic acids. The method features mild conditions, an unprecedented substrate scope, and functional group compatibility.
Article
Chemistry, Multidisciplinary
Nozomi Tomioka, Shinkoh Nanbu, Tomoyo Misawa-Suzuki, Hirotaka Nagao
Summary: Ruthenium complexes were oxidized by cerium sulfate to form new complexes through N-C bond formation between two aniline ligands and the ruthenium center.
Article
Chemistry, Organic
Hyun Ji Jeon, Su Min Park, Yu Lim Lee, Sang-gi Lee
Summary: The palladium-catalyzed divergent asymmetric synthesis of chiral spiro-furanindoline derivatives is described. The zwitterionic alkoxy pi-allyl Pd(II) intermediate, generated catalytically from vinyl ethylene carbonate (VEC), could undergo ligand-controlled enantio-and diastereoselective dipolar [3 + 2] spiroannulation with indole-based azadienes to afford the optically active spiro-furanindolines embedding an all-carbon quaternary stereocenter in high yields (up to 99%) with good to excellent stereoselectivities (up to 99% ee and up to >94:6 dr).
Article
Chemistry, Organic
Guangxing Pan, Shaoheng Qin, Dawen Xu, Fritz E. Kuehn, Hao Guo
Summary: The photoinduced pericyclic cascade reaction described in this study provides a novel approach to oxabicyclo[4.2.0]octenes, involving [2 + 2]-photocycloaddition, base-promoted elimination, retro-4p-electrocyclization, [1,5]-H shift, and 4p-electrocyclization processes. This reaction exhibits broad substrate scope, good functional group tolerance, and excellent diastereoselectivity.
Article
Chemistry, Organic
Atif Sharif, Huai-Ri Sun, Wen-Lei Xu, Bo-Bo Gou, Lan Yang, Yu Li, Jie Chen, Ling Zhou
Summary: An efficient dehydrogenative inverse electron demand Diels-Alder reaction has been reported for the first time, providing a broad substrate scope and excellent yields in the synthesis of biologically valuable pyranones.
Review
Chemistry, Multidisciplinary
Didier A. Bilodeau, Kaitlyn D. Margison, Mariam Serhan, John Paul Pezacki
Summary: Bioorthogonal chemical reactions involving nitrones have been optimized for efficient incorporation of unnatural functionality into living systems, with fast reaction rates. These reactions provide versatile tools for probing biological systems and have potential applications in biology.
Article
Chemistry, Multidisciplinary
Shu-Shan Gao, Marc Garcia-Borras, Joyann S. Barber, Yang Hai, Abing Duan, Neil K. Garg, K. N. Houk, Yi Tang
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2017)
Article
Biotechnology & Applied Microbiology
John M. Billingsley, Anthony B. DeNicola, Joyann S. Barber, Man-Cheng Tang, Joe Horecka, Angela Chu, Neil K. Garg, Yi Tang
METABOLIC ENGINEERING
(2017)
Article
Chemistry, Organic
Francesca M. Ippoliti, Joyann S. Barber, Yi Tang, Neil K. Garg
JOURNAL OF ORGANIC CHEMISTRY
(2018)
Article
Chemistry, Multidisciplinary
Joyann S. Barber, Michael M. Yamano, Melissa Ramirez, Evan R. Darzi, Rachel R. Knapp, Fang Liu, K. N. Houk, Neil K. Garg
Article
Chemistry, Multidisciplinary
Evan R. Darzi, Joyann S. Barber, Neil K. Garg
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2019)
Article
Chemistry, Organic
Joyann S. Barber, Stephanie Scales, Michelle Tran-Dube, Fen Wang, Neal W. Sach, Louise Bernier, Michael R. Collins, JinJiang Zhu, Indrawan J. McAlpine, Ryan L. Patman
Article
Multidisciplinary Sciences
Masao Ohashi, Cooper S. Jamieson, Yujuan Cai, Dan Tan, Daiki Kanayama, Man-Cheng Tang, Sarah M. Anthony, Jason V. Chari, Joyann S. Barber, Elias Picazo, Thomas B. Kakule, Shugeng Cao, Neil K. Garg, Jiahai Zhou, K. N. Houk, Yi Tang
Article
Chemistry, Organic
Joyann S. Barber, Dehuan Kong, Wei Li, Indrawan J. McAlpine, Sajiv K. Nair, Sylvie K. Sakata, Nicole Sun, Ryan L. Patman
Summary: In this study, a simple and robust procedure for the Rh(III)-catalyzed [4+2] cycloaddition of feedstock gases enabled through C-H activation is described. A diverse set of 3,4-dihydroisoquinolones and 3-methylisoquinolones have been prepared in good to excellent yields. The effects of using ethylene and propyne as coupling partners on C-H site selectivity have also been explored with a representative set of substrates and discussed in detail.
Article
Multidisciplinary Sciences
Hui-Qi Ni, Ilia Kevlishvili, Pranali G. Bedekar, Joyann S. Barber, Shouliang Yang, Michelle Tran-Dube, Andrew M. Romine, Hou-Xiang Lu, Indrawan J. McAlpine, Peng Liu, Keary M. Engle
NATURE COMMUNICATIONS
(2020)
Article
Chemistry, Multidisciplinary
Hui-Qi Ni, Phillippa Cooper, Shouliang Yang, Fen Wang, Neal Sach, Pranali G. Bedekar, Joyann S. Donaldson, Michelle Tran-Dube, Indrawan J. McAlpine, Keary M. Engle
Summary: In this study, we evaluated different ambiphilic organohalides for their participation in anti-selective carbocyclic or heterocyclic annulation with non-conjugated alkenyl amides under Pd-II/Pd-IV catalysis. By optimizing the reaction conditions, we developed protocols for the synthesis of various carbocyclic or heterocyclic compounds. We also demonstrated the reactivity of otherwise unreactive ambiphilic haloketones through Pd-II/amine co-catalysis. This method proceeds via a distinct Pd-II/Pd-IV mechanism, resulting in unique reactivity and selectivity patterns.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Multidisciplinary Sciences
Francesca M. Ippoliti, Nathan J. Adamson, Laura G. Wonilowicz, Daniel J. Nasrallah, Evan R. Darzi, Joyann S. Donaldson, Neil K. Garg
Summary: Small rings containing allenes are unconventional compounds that have been known since the 1960s. Despite having similar discovery time to benzyne and advantageous features, strained cyclic allenes have been underutilized in chemical synthesis. This study presents a concise total synthesis of lissodendoric acid A, a manzamine alkaloid, through the selective trapping of a short-lived cyclic allene intermediate. This synthetic approach efficiently constructs the azadecalin framework, resulting in a 12-step total synthesis with a 0.8% overall yield.
Article
Chemistry, Organic
Joyann S. Barber, Alexander Burtea, Michael R. Collins, Michelle Tran-Dube, Ryan L. Patman, Stephanie Scales, Graham Smith, Jillian E. Spangler, Fen Wang, Wei Wang, Shouliang Yang, JinJiang Zhu, T. Patrick Montgomery
Article
Chemistry, Organic
Francesca M. Ippoliti, Joyann S. Barber, Neil K. Garg