Article
Chemistry, Organic
Cong-Hui Gao, Lei Yu, Xin-Yue Wu, Hong-Lin Wan, Wei Tan, Feng Shi
Summary: A tandem cyclization/addition reaction of 1,4-enediones with 2-naphthols was catalyzed by Bronsted acid, leading to the synthesis of a series of 2-furylmethylnaphthalenes with high yields (up to 98%). Control experiments provided insights into the possible reaction pathway and activation mode, contributing to the understanding of Bronsted acid catalysis and tandem reactions.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Andreas Schneider, Christian Curado, Thomas B. Lystbaek, Silvia Osuna, Bernhard Hauer
Summary: This study uncovers the catalytic potential of squalene-hopene cyclase (SHC) and demonstrates a 397-fold improvement in catalytic performance through tailored mutations. The study also identifies terpene-induced inactivation as a major limitation and proposes a feeding strategy to overcome this limitation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Multidisciplinary Sciences
Min Jin, Congyun Tang, Yingying Li, Shuai Yang, Ying-Tao Yang, Lin Peng, Xiao-Nian Li, Wenjing Zhang, Zhili Zuo, Fabien Gagosz, Liang-Liang Wang
Summary: In this study, the authors present a catalytic asymmetric inverse-electron-demand-hetero-Diels-Alder reaction between neutral alkenes and alpha, beta-unsaturated ketones or aldehydes using a chiral phosphoric acid catalyst. This complex transformation allows for the formation of chiral fused heterocycles containing a central tetrahydropyran ring with high regio-, diastereo- and enantioselectivity. The stereocontrol achieved in this process is attributed to a key remote double hydrogen atom bonding interaction between the linear substrate and the catalyst.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Marta Solas, Samuel Suarez-Pantiga, Roberto Sanz
Summary: This study describes the asymmetric synthesis of cyclopentachromenones from gold-catalyzed reaction of readily available skipped alkenynones. The cascade reaction involves an initial anti-Michael hydroarylation and a subsequent Nazarov cyclization. Excellent enantiomeric ratios and chemical yields are achieved under mild reaction conditions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Brijesh Patel, Shilpa Dabas, Parth Patel, Saravanan Subramanian
Summary: One of the fundamental aims in catalysis research is to understand the factors that contribute to the superior performance of a certain scaffold as a catalyst. In this study, a simple and scalable electrostatically tuned phenol (ETP) was used as an organic catalyst for the transfer hydrogenation of N-arenes. The charged environment plays a crucial role in the catalytic transformation, and the biomimetic catalyst showed promising catalytic activity.
Article
Chemistry, Organic
Gao-feng Yang, Guang-xun Li, Jin Huang, Ding-qiang Fu, Xiao-kang Nie, Xin Cui, Jin-zhong Zhao, Zhuo Tang
Summary: An unexpected tandem cyclization/transfer hydrogenation reaction was developed for the synthesis of chiral 2,3-disubstituted 1,5-benzodiazepines. The reaction, catalyzed by chiral phosphoric acid, exhibited moderate yields, good selectivities, and high enantiomeric ratios, providing a new method for the synthesis of this class of compounds.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Applied
Wan-Fa Tian, Yao Zhu, Yong-Qin He, Mei Wang, Xian-Rong Song, Jiang Bai, Qiang Xiao
Summary: A novel hydroxyl assisted, photoredox/cobalt co-catalyzed semi-hydrogenation and tandem cyclization reaction has been developed for the direct assembly of 2,3-dihydrobenzofurans, with moderate to good yields obtained for a variety of 2-propynolphenols under mild conditions. Mechanistic studies revealed the essential role of the alcoholic hydroxyl group and proposed a key low-valent cobalt catalyzed intramolecular hydroetherification of alkene.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Sachin R. Shirsath, Sagar M. Chandgude, M. Muthukrishnan
Summary: An iron(III) catalyzed tandem ring opening/1,6-conjugate addition of cyclopropanols to p-quinone methides leading to gamma,gamma-diaryl ketones has been reported. This novel catalytic protocol provides an efficient method to access gamma,gamma-diaryl ketone derivatives with high yields and functional group tolerance. Importantly, these ketones can be further functionalized to generate a versatile set of useful products.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
James E. Gillespie, Alexander Fanourakis, Robert J. Phipps
Summary: Ion-pairing interactions can be used to control selectivity in chemical reactions, especially in C-H bond functionalization processes. This emerging field is of great interest to chemists in both industry and academia.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Biochemistry & Molecular Biology
Anna N. Philippova, Daria V. Vorobyeva, Pavel S. Gribanov, Ivan A. Godovikov, Sergey N. Osipov
Summary: An efficient method for the selective preparation of trifluoromethyl-substituted azepin-2-carboxylates and their phosphorous analogues has been developed via Cu(I)-catalyzed tandem amination/cyclization reaction of functionalized allenynes with primary and secondary amines.
Article
Chemistry, Organic
Dan Liu, Yue Zhao, Frederic W. Patureau
Summary: A practical NaI/PPh3-catalyzed decarboxylative radical cascade cyclization of N-arylacrylamides with redox-active esters is reported in this study, which is mediated by visible light irradiation. A wide range of substrates derived from ubiquitous carboxylic acids, including alpha-amino acids, were successfully synthesized under this transition-metal-free and cost-effective synthetic method. The mechanistic experiments suggest a radical mechanism for this reaction.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Zeng Gao, Jinlong Qian, Huameng Yang, Jinlong Zhang, Gaoxi Jiang
Summary: Two approaches involving intramolecular and intermolecular cyclization were developed for the construction of a series of benzo[f]pyrrolo[1,2-a][1,4]azepines using Bronsted acid catalysts. The intramolecular dehydroxylation/ring closure reaction and intermolecular addition reaction both provided high yields of the desired compounds.
Article
Chemistry, Physical
Hideyuki Ishihara, Jianhao Huang, Takuya Mochizuki, Manabu Hatano, Kazuaki Ishihara
Summary: A highly enantio- and diastereoselective carbonyl-ene cyclization was developed using chiral Lewis acid-assisted chiral Bronsted acid (LBA) catalysts, demonstrating high selectivity in both standard and tandem reactions. Mechanistic examinations propose a stepwise reaction pathway involving tertiary carbocation intermediates.
Article
Engineering, Environmental
Zishang Tian, Xiaojie Shao, Jiaojiao Zhang, Lijuan Su, Yingxiong Wang, Tiansheng Deng, Yuqi Wang, Xianglin Hou
Summary: PPTA, with its highly symmetrical structure, has amide bonds that can be selectively cleaved by strong base catalysts. The efficient catalytic system developed in this work allowed for controlled degradation of waste PPTA, resulting in high yields of TPA and PPD. The study also identified the important factors influencing the depolymerization of PPTA, such as the wettability of alcohols on PPTA monofilament.
Article
Chemistry, Organic
Thomas Mies, Andrew J. P. White, Philip J. Parsons, Anthony G. M. Barrett
Summary: This study describes the synthesis of a range of hongoquercins using gold-catalyzed enyne cyclization reactions, and the preparation of the parent enyne resorcylate precursors through several steps including regioselective acylation, Tsuji-Trost allylic decarboxylative rearrangement, and aromatization. The dioxinone keto ester was prepared in 6 steps from geraniol through allylic functionalization and alkyne synthesis.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Andrea Chaves-Pouso, Andres M. Alvarez-Constantino, Martin Fananas-Mastral
Summary: Allylic gem-dichlorides can be efficient substrates for catalytic asymmetric allylboration of alkynes. The method generates chiral skipped dienes with excellent levels of chemo-, regio- enantio- and diastereoselectivity, making them versatile building blocks for the synthesis of optically active compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Andrea Chaves-Pouso, Andres M. Alvarez-Constantino, Martin Fananas-Mastral
Summary: In this Communication, Martin Fananas-Mastral et al. report an enantio- and diastereoselective copper-catalyzed allylboration of alkynes with allylic gem-dichlorides.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Borja Perez-Saavedra, Alvaro Velasco-Rubio, Eva Rivera-Chao, Jesus A. Varela, Carlos Saa, Martin Fananas-Mastral
Summary: Functionalized alicyclic amines are crucial for synthesizing bioactive compounds and drugs. This study presents a novel copper-catalyzed method for transforming O-benzoyl hydroxylamines into alpha-functionalized cyclic secondary amines, using unique additives to inhibit competing reactions. The method exhibits high selectivity and efficiency.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Organic
Nuria Vazquez-Galinanes, Isabel Velo-Heleno, Martin Fananas-Mastral
Summary: A method for the use of vinyl epoxides in catalytic allylboration of alkynes is described, which allows for the synthesis of bifunctional skipped dienes bearing both an allylic alcohol and an alkenylboronate from simple starting materials with high regio- and stereoselectivity. These products show versatile reactivity and can be converted into cyclic boron compounds and polyenes.
Article
Chemistry, Organic
Andres M. Alvarez-Constantino, Andrea Alvarez-Perez, Jesus A. Varela, Giuseppe Sciortino, Gregori Ujaque, Carlos Saa
Summary: A new Ru-catalyzed intramolecular oxidative amida-tion reaction has been developed, which efficiently synthesizes medium-sized euro- and zeta- lactams but not common t5-lactams. DFT studies reveal the important role of chain length between the amine and alkyne functionalities in this reaction.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Alejandro Suarez-Lustres, Nuria Martinez-Yanez, Alvaro Velasco-Rubio, Jesus A. Varela, Carlos Saa
Summary: The first Pd-catalyzed [5 + 2] rollover annulation of 1-benzylpyrazoles with alkynes has been developed to assemble 10H-benzo[e]pyrazolo-[1,5-a]azepines (tricyclic 2-benzazepines). The rollover annulation involves twofold C-H activation of aryl and heteroaryl C-sp(2)-H bonds (C-H/C-H) of 1-benzylpyrazoles (five-atom partners) and alkynes, resulting in [5 + 2] annulated compounds.
Article
Chemistry, Multidisciplinary
Eugenia Miguel-Casan, Mohanad D. Darawsheh, Victor Farina-Torres, Inigo J. Vitorica-Yrezabal, Eduardo Andres-Garcia, Martin Fananas-Mastral, Guillermo Minguez Espallargas
Summary: This study successfully synthesized a stable palladium-based metal-organic framework and demonstrated its excellent catalytic activity and selectivity in the Suzuki-Miyaura allylation of aryl and alkyl boronates. This has important implications for the development of efficient catalysts.
Article
Chemistry, Physical
Martin Pineiro-Suarez, Andres M. Alvarez-Constantin, Martin Fananas-Mastral
Summary: A catalytic asymmetric reaction involving allyl copper species with allylic gem-dichloride is reported, providing high selectivity chiral internal 1,5-dienes with (Z)-configured alkenyl boronate and alkenyl chloride. The synthetic utility of the products is demonstrated by synthesizing optically active compounds. DFT calculations reveal noncovalent substrate-ligand interactions accounting for the selectivity outcome.
Article
Chemistry, Physical
Ignacio Benito-Gomez, Luis Mendez, Jaime Suarez, Jimena D. D. Gorfinkiel, Ismanuel Rabadan
Summary: We have investigated the dissociation of a resonant state in low energy electron scattering from H2O+. Specifically, we studied the second triplet resonance above the B & SIM;2A' ${{{\tilde{\rm {B}}}}\;<^>2 {\rm{A{<^>\prime}}}}$ (B & SIM;2B2) ${{\rm{(\tilde{B}}}\;<^>2 {\rm{B}}_2 )}}$ state of H2O+. Our results showed that the probability for dissociative recombination (DR) was about 38%, while the probability for dissociative excitation (DE) was negligible.
Article
Chemistry, Physical
Andrea Chaves-Pouso, Eva Rivera-Chao, Martin Fananas-Mastral
Summary: This Perspective covers the developments in the area of catalytic allylboration of alkynes and highlights the key features that have allowed for the control of the regio-, diastereo-, and enantioselectivity in these transformations.
Article
Chemistry, Multidisciplinary
Alvaro Velasco-Rubio, Pol Martinez-Balart, Andres M. Alvarez-Constantino, Martin Fananas-Mastral
Summary: Direct functionalization of alkanes is a significant challenge in developing efficient and clean C-C bond forming reactions due to the low reactivity of aliphatic C-H bonds. Photocatalytic processes using hydrogen atom transfer C-H bond activation strategies have emerged as useful tools to activate and functionalize these inert compounds. This article summarizes the main achievements in this field for developing C-C bond forming reactions and discusses the key mechanistic features enabling these transformations.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Alvaro Velasco-Rubio, Jesus A. Varela, Carlos Saa
Summary: The Pd-catalyzed allylic C-H activation of simple olefins allows for the easy synthesis of seven-membered N,O-heterocycles such as 1,4-BZOs, 1,4-BZDs, and 1,4-oxazepanes in good to excellent yields. The straightforward derivatization of the olefinated 1,4-BZO demonstrates the synthetic utility of this methodology.
CHEMICAL COMMUNICATIONS
(2021)
