Article
Chemistry, Multidisciplinary
Shuai Liu, Yangen Huang, Juan Wang, Feng-Ling Qing, Xiu-Hua Xu
Summary: This study reports a method for the design and synthesis of novel N-Cbz- and N-Boc-N-trifluoromethyl hydroxylamine reagents using silver-mediated oxidative trifluoromethylation. These reagents have been successfully applied to incorporate a NCF3 moiety into commonly used unsaturated substrates, enabling efficient and regioselective C-H trifluoromethylamination. Additionally, a variety of substrates can undergo tandem trifluoromethylamination/functionalization to deliver structurally diverse N-trifluoromethyl aliphatic and heteroaromatic amines.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Review
Chemistry, Organic
Lodsna Borkotoky, Ram Awatar Maurya
Summary: Organic azides exhibit versatile reactivity that can be used to synthesize a variety of high-valued N-heterocycles through alpha-azidoketones and esters.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Bijay Ketan Das, Tanumay Sarkar, Prabhat Kumar Maharana, Subhradeep Kar, Tharmalingam Punniyamurthy
Summary: In this study, stereospecific cascade C-N and C-O bonds formation of oxiranes with N-propargylamines was achieved using Zn/Ag relay catalysis, leading to the synthesis of functionalized dihydrooxazines. The reaction exhibited excellent tolerance towards various functional groups and was scalable for practical applications.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Ru-Jie Yan, Bao-Xin Liu, Yuan Hu, Wei Du, Ying-Chun Chen
Summary: Zwitterionic N-allylic ylide species are generated from Morita-Baylis-Hillman carbonates of trifluoromethyl ketones and acrylonitrile under the catalysis of cinchona-derived tertiary amines, and participate in switchable asymmetric [3+2] or [4+1] annulations with 1-azadienes in chemo-, regio-, and stereodivergent manners to construct frameworks with trifluoromethylated all-carbon quaternary stereogenic centre or tetrasubstituted alkene moiety in good yields with excellent enantioselectivity.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Bastian L. Springer, Kristina Holzschneider, Fabian Mohr, Stefan F. Kirsch
Summary: A new synthetic route for phenanthro[9,10-d]imidazoles is reported. The target compounds were synthesized through the aminolysis of readily accessible 10,10-diazidophenanthren-9(10H)-one with nucleophilic amines, followed by a self-condensation. X-ray single crystallography was used to determine the molecular structures, and the optical properties of the material were described.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Applied
Tongtong Zheng, Zhe Feng, Jun-An Ma, Chi Wai Cheung
Summary: We describe a cascade transformation of nitroarenes and trimethylamine using dual nickel/photoredox catalysis, leading to the synthesis of N-formyl N,N'-diaryl ethylenediamines. The reaction involves multiple C-N and C-C coupling events based on nitrogen and α-aminomethyl radicals derived from the starting materials. The obtained products can further undergo hydrolysis for further derivatizations.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Melania Gomez-Martinez, Maria del Carmen Perez-Aguilar, Dariusz G. Piekarski, Constantin G. Daniliuc, Olga Garcia Mancheno
Summary: An enantioselective anion-binding organocatalytic approach using versatile N,N-dialkylhydrazones as polarity-reversed nucleophiles is presented. A highly ordered hydrogen-bond network was envisioned between a CF3-substituted triazole-based multidentate HB-donor catalyst, the ionic substrate, and the hydrazone in a supramolecular chiral ion-pair complex. Experimental and computational studies supported the formation of this network, showing the crucial role of the anion as a template unit. The asymmetric reaction provided highly enantiomerically enriched hydrazones that could be further derivatized to value-added compounds with up to three stereocenters.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Florian Puls, Philipp Linke, Olga Kataeva, Hans-Joachim Knoelker
Summary: This paper describes a convenient method for the oxidation of olefins to ketones using Fe(dbm)(3) or a combination of iron(II) chloride and neocuproine as catalysts and phenylsilane as an additive. The reactions are efficient and have a high yield and selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Rene Hommelsheim, Robin van Nahl, Lena M. Hanek, Jas S. Ward, Kari Rissanen, Carsten Bolm
Summary: This study reports a palladium-catalyzed domino reaction that enables the synthesis of 3-amino-substituted 1,2,4-benzothiadiazine 1,1-dioxides at room temperature. The method demonstrates good substrate compatibility and mild reaction conditions.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Chang-Ming You, Cheng Huang, Sheng Tang, Peng Xiao, Shengchun Wang, Zhenhong Wei, Aiwen Lei, Hu Cai
Summary: Direct N-allylation of azoles with hydrogen evolution has been achieved by the synergistic combination of organic photocatalysis and cobalt catalysis. This protocol eliminates the need for stoichiometric oxidants and prefunctionalization of alkenes, and produces hydrogen (H2) as a byproduct. The transformation highlights high step and atom economy, high efficiency, and broad functional group tolerance, opening up a pathway for valuable C-N bond formation in heterocyclic chemistry.
Article
Chemistry, Multidisciplinary
Ru Zhong Zhang, Ru Xue Zhang, Shuang Wang, Cong Xu, Wei Guan, Mang Wang
Summary: In this study, an alternative and scalable cyclization strategy based on NCF3-containing synthons was used to construct N-CF3 azoles. This approach allows for the divergent synthesis of N-trifluoromethylated tetrazoles, imidazoles, and 1,2,3-triazoles using various dipoles. The introduction of CF3 onto the nitrogen of heterocycles provides a direct route to such motifs, overcoming the limitations of traditional methods.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Applied
Zi-Kui Liu, Quan-Qing Zhao, Yang Gao, Ye-Xing Hou, Xiao-Qiang Hu
Summary: Organic azides, as highly reactive building blocks, are widely used in the assembly of N-containing heterocycles. Transition metal-catalyzed C(sp(2))-H amination/annulation of organic azides provides a powerful tool for the synthesis of biologically important heterocyclic frameworks. Progress on organic azides-mediated C(sp(2))-H amination/annulation for N-heterocycle synthesis enabled by transition metal catalysts is discussed in this review.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Rafael Ballesteros-Garrido, Nerea Gonzalez-Sanchis, Paula Perez-Quilez, Delia Belleza, Anna Flor-Sanchez, Rafael Ballesteros
Summary: Nitrogen-containing polyaromatic compounds have been synthesized in one step by combining diols and anthracenyl or naphthyl amines via acceptorless dehydrogenative condensation using ZnO and Pt/Al2O3 as heterogeneous catalysts.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
Srimanta Manna, Wei-Jun Kong, Jan-E Backvall
Summary: This study presents an iron(II)-catalyzed biomimetic oxidation of N-heterocycles under aerobic conditions, inspired by oxidations in the respiratory chain. The method utilizes environmentally friendly and inexpensive catalysts, delivering important heterocycles in good-to-excellent yields with a broad substrate scope.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Organic
Anna L. Samsonenko, Anastasia S. Kostyuchenko, Tatyana Yu. Zheleznova, Vladislav Yu. Shuvalov, Igor S. Vlasov, Alexander S. Fisyuk
Summary: This article discusses the development of practical methods for synthesizing 4-azido-5-arylthiophene-2-carboxylates and 4-amino-5-arylthiophene-2-carboxylates using the Fiesselmann reaction. The decomposition of 4-azido-5-arylthiophene-2-carboxylates through photochemical and thermal processes, including microwave-assisted decomposition, was studied to synthesize fused 4H-thieno[3,2-b]pyrrole derivatives. These proposed methods allow for the synthesis of functionalized heteroacenes, which are important building blocks for organic semiconductors.
SYNTHESIS-STUTTGART
(2022)
Review
Chemistry, Multidisciplinary
Qixue Qin, Zengrui Cheng, Ning Jiao
Summary: Trifluoromethanesulfonic anhydride (Tf2O) is widely used in synthetic organic chemistry for various conversions and activations. It has shown promising results as an activator for nitrogen-containing heterocycles, nitriles, and nitro groups. Additionally, Tf2O is an efficient reagent for radical trifluoromethylation and trifluoromethylthiolation reactions. This review summarizes the recent progress and potential applications of Tf2O in organic synthesis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Yijie Li, Yu-Hsuan Shen, Alec M. M. Esper, John R. R. Tidwell, Adam S. S. Veige, Caleb D. D. Martin
Summary: The reaction of Ph3PAuN3 with 9-Ph-9-borafluorene resulted in the complexation of azide to boron, while a gold acetylide reacted with 9-Ph-9-borafluorene to insert the acetylide carbon and form a six-membered boracycle with an exocyclic double bond.
DALTON TRANSACTIONS
(2023)
Article
Engineering, Electrical & Electronic
Chenji Guo, Jiayang Xu, Jiannan Xu, Huali Lu, Hui Hao, Hua Zhao, Peng Wang, Hongpu Li
Summary: Orbital-angular-momentum (OAM) beams-based interferometers have attracted significant interest and found various applications in optical precision measurement. In this study, an all-fiber OAM beams-based interferometer was proposed and experimentally demonstrated, utilizing helical long-period fiber gratings (HLPGs) to generate conjugated OAM beams for testing and referencing. The interferograms obtained had polarization independence, robustness, and were particularly suitable for phase-demodulation in the azimuthal angle domain. The proposed interferometer showed high sensitivity and measurement accuracy for temperature and strain, making it suitable for ultra-high precision and sensing measurements.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Manjur O. Akram, John R. Tidwell, Jason L. Dutton, Caleb D. Martin
Summary: This passage describes a Lewis superacid called bis(1-methyl-ortho-carboranyl)borane, which can be rapidly synthesized in two steps. It is a highly effective hydroboration reagent capable of B-H addition to alkenes, alkynes, and cyclopropanes. To date, it is the first identified Lewis superacidic secondary borane and the most reactive neutral hydroboration reagent.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Engineering, Electrical & Electronic
Zhen Zhang, Heng Zhang, Kaiyue Gao, Jinxin Wu, Hui Hao, Hua Zhao, Peng Wang, Hongpu Li
Summary: A temperature-insensitive torsion and strain sensor based on a helical long-period fiber grating (HLPG) is proposed and demonstrated. The sensor utilizes a second-order HLPG in a thinned four-mode fiber to achieve simultaneous measurement of torsion and strain. The sensor's maximum torsion sensitivity is 665 pm/(rad/m) and maximum strain sensitivity is -5.42 pm/με, which are significantly higher than those of conventional long-period fiber grating (LPG)-based sensors. Additionally, the sensor exhibits a temperature sensitivity of 13.7 pm/°C, which is about 4 times lower than that of conventional LPGs.
IEEE JOURNAL OF QUANTUM ELECTRONICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Masilamani Tamizmani, John R. Tidwell, Eric W. Reinheimer, Brian M. Lindley, Caleb D. Martin
Summary: Neutral triple-decker iron and cobalt complexes with a bridging 1,2-diboratabenzene ligand were synthesized by reacting a dilithium 1,2-diboratabenzene reagent with [Cp*FeCl]2 and [Cp*CoCl]2, respectively. These complexes are the first examples of the ligand bridging two metals, although 1,2-diboratabenzene metal complexes are already known.
INORGANIC CHEMISTRY
(2023)
Article
Engineering, Electrical & Electronic
Chengliang Zhu, Qingxia Piao, Lei Wang, Zhenhao Bing, Yong Zhao, Hua Zhao, Hongpu Li
Summary: An ultra-wideband orbital-angular-momentum (OAM) mode generator based on a helical long period fiber grating (HLPG) written in a graded-index few-mode fiber (GIFMF) has been proposed and demonstrated. Unlike previous HLPG-based broadband OAM generators, which operated at wavelengths close to the dispersion-turning point (DTP), the GIFMF-based HLPG proposed in this study operates at wavelengths far from the DTP, enabling the production of a ultra-wideband OAM mode generator with high conversion efficiency and flexibility in controlling the central wavelength. A first-order OAM mode generator with a central wavelength of approximately 1510 nm, a bandwidth of approximately 235 nm, and a conversion efficiency larger than 99% (approximately 20.7 dB) has been successfully obtained, marking the first practical demonstration of the GIFMF-based HLPG.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Sanjay Dutta, Caleb D. Martin
Summary: This study reveals the elastic and plastic bending, as well as temperature-induced reversible and irreversible structural transformations, in single-molecule bicyclic phosphates, which are rare in globular systems. The observed behaviors are rationalized through structure-property analyses using single-crystal X-ray diffraction and calculations. Overall, this research identifies this class of molecules as promising candidates for flexible ferroelectric materials.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Engineering, Electrical & Electronic
Meng Zhang, Chengliang Zhu, Hongpu Li
Summary: This study reveals the underlying mechanism for mode coupling and propagation in a strongly-coupled few-period long-period fiber grating (LPG), based on the idea that it can be considered as cascaded and phase-matched Mach-Zehnder interferometers. The proposed mechanism and analysis method can also be applied to conventional LPGs, opening up new possibilities for design and fabrication of other types of LPGs such as mode converters, multichannel, phase-shift, and high-order LPGs.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Chengliang Zhu, Shuai Huang, Chengfeng Tang, Gang Yang, Yong Zhao, Hongpu Li
Summary: A miniature temperature-independent curvature sensor was proposed and prepared using a phase-shifted long-period fiber grating fabricated from deeply tapered conventional single-mode fibers. A demonstration of a sensor made from a phase-shifted deeply tapered long-period grating with a length of 3.4 mm and a maximum curvature sensitivity of 12.05 nm/m(-1) was successful. The proposed curvature sensor has the characteristics of temperature independence, high sensitivity, high reliability, miniature size, and low cost, making it potentially useful in structural health monitoring, especially in the medical industry and shape reconstruction.
IEEE SENSORS JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Manjur O. Akram, Caleb D. Martin, Jason L. Dutton
Summary: The Lewis acidity of primary, secondary, and tertiary boranes with phenyl, pentafluorophenyl, and all three isomers of the icosahedral carboranes was studied by calculating their affinities for fluoride, hydride, and ammonia, as well as their electrophilicity indices and LUMO energies. It was found that the substituent effects on Lewis acidity followed the trend of ortho-carborane > meta-carborane > para-carborane > C6F5 > C6H5.
INORGANIC CHEMISTRY
(2023)
Article
Engineering, Electrical & Electronic
Chengliang Zhu, Shuai Huang, Xinyue Meng, Yong Zhao, Hongpu Li
Summary: Deeply-tapered long-period fiber gratings (DT-LPFGs) have been fabricated using the cylindrical-lens-assisted CO2 laser technique. The DT-LPFG demonstrates high coupling efficiency and low polarization-dependence, making it suitable for the production of ultrashort yet strong LPFGs and highly sensitive transverse load sensors.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Optics
Zhang Meng, Naruya Mochzuki, Shiryu Oiwa, Hua Zhao, Peng Wang, Chengliang Zhu, Hongpu Li
Summary: In this study, a full C-band covered and DWDM channelized OAM mode generator is proposed and experimentally demonstrated. The generator utilizes a broadband helical long-period fiber grating (HLPG) combined with a phase-only sampled multichannel fiber Bragg grating (MFBG). The demonstrated generator shows high conversion efficiency, wide bandwidth, and uniformity between channels, and has potential applications in various fields.
Article
Optics
Hua Zhao, Jiannan Xu, Yuanyuan Hao, Jiayang Xu, Huali Lu, Hui Hao, Ting Zhao, Pengfei Li, Peng Wang, Hongpu Li
Summary: In this study, it is demonstrated theoretically and experimentally that the convolutional neural network (CNN) combined with residual blocks and regression methods can accurately and quickly reconstruct the OAM spectrum of hybrid OAM modes, regardless of the consistency of the order indices in both azimuthal and radial directions. The mean errors of recognized parameters for hybrid OAM modes in a 4-mode fiber (4MF) and a 6-mode fiber (6MF) are smaller than 0.003 and 0.008, respectively. This is the first time that all OAM modes in 4MFs or 6MFs can be accurately and quickly recognized using the deep learning method.
Article
Chemistry, Multidisciplinary
Ida M. DiMucci, Charles J. Titus, Dennis Nordlund, James R. Bour, Eugene Chong, Dylan P. Grigas, Chi-Herng Hu, Mikhail D. Kosobokov, Caleb D. Martin, Liviu M. Mirica, Noel Nebra, David A. Vicic, Lydia L. Yorks, Sam Yruegas, Samantha N. MacMillan, Jason Shearer, Kyle M. Lancaster
Summary: The Nickel K- and L-2, L-3-edge X-ray absorption spectra (XAS) of 16 complexes and complex ions with nickel centers were studied. It was found that the K-edge XAS alone cannot accurately determine the physical oxidation state of these Ni complexes. On the other hand, the L-2, L-3-edge XAS showed that the physical d-counts of the Ni-IV compounds measured were higher than the d(6) count implied by the oxidation state formalism. Computational analysis of 8 additional complexes confirmed this phenomenon.
