Article
Chemistry, Physical
Yuan Xue, Han Seul Park, Chao Jiang, Jin-Quan Yu
Summary: In this study, a Pd(II)-catalyzed beta-C(sp(3))-H nitrooxylation of ketones and native amides was reported. The use of fine-tuned removable aminooxyamide auxiliary enabled beta-C(sp(3))-H functionalization of various aliphatic ketones. Palladacycle intermediates were isolated to elucidate the reaction mechanism for ketones C(sp(3))-H activation with the L,X-type imino-amide directing group.
Article
Chemistry, Applied
Haeun Park, Sunwoo Lee
Summary: The Friedel-Crafts acylation reaction was conducted between activated amides and arenes using [Pd(cinnamyl)Cl](2) and Cu(OTf)(2) as catalysts. A variety of N-phenyl-N-tosylbenzamides with substituted phenyl rings underwent reactions with different arenes, including mesitylene, toluene, anisole, 4-tert-butylbenzene, o-xylene, m-xylene, and p-xylene, resulting in the corresponding diaryl ketones with yields ranging from 49% to 89%.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Xiaoyu He, Sengui Hu, Yuxuan Xiao, Lin Yu, Wengui Duan
Summary: A practical protocol for the synthesis of ketones by Pd-catalyzed cross-coupling of phenol derivatives with nitroalkanes followed by a Nef-type reaction has been developed. This sustainable method avoids the use of organometallics and organic halides and is compatible with various functional groups.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Wei-Ze Li, Zhong-Xia Wang
Summary: The alpha-alkylation of methyldiarylphosphine oxides with (hetero)arylmethyl alcohols was successfully achieved under nickel catalysis, yielding 30-90% of the desired products. Various arylmethyl and heteroarylmethyl alcohols can be utilized and functional groups on the aromatic rings are well tolerated, making it a versatile transformation. The reaction conditions are also applicable for the alpha-alkylation of dialkyl methylphosphonates.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Tianhao Xu, Xingyu Zhou, Xiong Xiao, Yan Yuan, Long Liu, Tianzeng Huang, Chunya Li, Zhi Tang, Tieqiao Chen
Summary: A nickel-catalyzed decarbonylative thioetherification of carboxylic acids with thiols has been developed, enabling the coupling of carboxylic acids with various thiols to produce thioether products. This reaction holds great synthetic value in the modification of bioactive molecules and the synthesis of certain acaricides.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Applied
Shuo He, Yujie Chen, Zhi-Bin Huang, Bao Li, Da-Qing Shi, Yingsheng Zhao
Summary: A palladium-catalyzed cross-coupling reaction between the ortho-C(sp(2)) atom of aromatic amines and aliphatic aziridines has been developed, enabling the construction of the O-aminophenethylamine skeleton via C-H activation. The reaction shows good substrate scope and can generate the O-aminophenethylamine skeleton in drugs or bioactive compounds in a one-step process.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Multidisciplinary Sciences
Chengtao Yue, Qi Xing, Peng Sun, Zelun Zhao, Hui Lv, Fuwei Li
Summary: The study successfully stabilized palladium in heterogeneous C-C bond formations by developing a novel bifunctional support catalyst, providing new experimental evidence for improving the stability of catalysts and enhancing the efficient applications of supported metal catalysts in advanced synthesis.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Narasingan Aravindan, Varathan Vinayagam, Masilamani Jeganmohan
Summary: An efficient ruthenium(II)-catalyzed tandem C-C/C-N bond formation has been developed for the synthesis of cis-fused dihydrobenzo[c]phenanthridinones using aryl amides and 7-azabenzonorbomadienes. The amide group acts as a directing and leaving group, providing easy access to pharmaceutically useful alkaloids. The reaction is compatible with various functional groups and the mechanism involves directing-group-assisted C-H activation.
Article
Chemistry, Physical
Dejiang Zhang, Ting Tang, Zhao Zhang, Liyuan Le, Zhi Xu, Hao Lu, Zhou Tong, Dishu Zeng, Wai-Yeung Wong, Shuang-Feng Yin, Arash Ghaderi, Nobuaki Kambe, Renhua Qiu
Summary: This study presents a general and efficient method for the synthesis of Sb-aryl and Sb-alkyl stibines through nickel-catalyzed cross-coupling reactions with organic halides. The method enables the high selectivity synthesis of complex biaryls and successfully synthesized various molecules, including drugs, with good yields.
Article
Multidisciplinary Sciences
Yufeng Sun, Jun Guo, Xuzhong Shen, Zhan Lu
Summary: In this study, a method for sequentially catalyzing alkynes with nitrogen and silicon atoms using a cobalt catalyst is presented. The method involves two catalytic cycles with different ligands, and demonstrates high efficiency, simple operation, and excellent functional group tolerance. The study also reveals a phenomenon of ligand relay, where certain ligands can capture metal ions from other ligands.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Kun-Long Song, Bin Wu, Wan-Er Gan, Wan-Chun Yang, Xiao-Bing Chen, Jian Cao, Li-Wen Xu
Summary: The palladium-catalyzed carbonylative C-C bond activation reaction described in this study involves C-C bond cleavage, ring-opening, and amino- or alkoxycarbonylation reactions on cyclobutanones. Two C-C bonds and one C-O or C-N bond are formed under gas-free conditions using CO surrogates, yielding a variety of indanones with ester or amide groups.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Miao Hu, Yong Jiang, Nan Sun, Baoxiang Hu, Zhenlu Shen, Xinquan Hu, Liqun Jin
Summary: An efficient method for Ni-catalyzed C3-alkylation of indoles using alcohols as alkylating reagents has been developed, with a stable binuclear nickel complex ligated by tetrahydroquinolin-8-one as the pre-catalyst. The transformation can accommodate a broad substrate scope including primary/secondary benzylic and aliphatic alcohols and substituted indoles, proceeding through a borrowing hydrogen pathway according to mechanistic studies.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Applied
Chen Chen, Jie Ding, Liying Liu, Yujie Huang, Bolin Zhu
Summary: The presented palladium-catalyzed domino cyclization/phosphorylation of gem-dibromoolefins utilizes H-phosphinates and secondary phosphine oxides as phosphine sources. Various phosphorylated heteroaromatics are obtained in moderate to good yields with broad functional group compatibility. This protocol enables multiple bond-forming events including C-X (X=O, N, S) and C-P bonds using readily available starting materials, and can be easily applied to large-scale preparation and late-stage functionalization.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Organic
Ryoma Shimazumi, Takuya Kodama, Mamoru Tobisu
Summary: The palladium-catalyzed reaction of N-allylamides with a tethered nucleophile leads to the removal of an amide moiety in the form of an isocyanate, which is then captured by a pendant nucleophile. This reaction involves the catalytic transposition of an amide group.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Organic
Biplab Keshari Pandia, Chidambaram Gunanathan
Summary: The unprecedented manganese-catalyzed direct alpha-alkenylation of amides using alcohols was reported, providing alpha,beta-unsaturated amides in moderate to good yields with excellent selectivity. Mechanistic studies showed that the selective olefination is facilitated by metal-ligand cooperation, resulting in water and dihydrogen as the only byproduct, making this catalytic transformation attractive, sustainable, and environmentally benign.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Analytical
Roman Picazo-Frutos, Quentin Stern, John W. Blanchard, Olivier Cala, Morgan Ceillier, Samuel F. Cousin, James Eills, Stuart J. Elliott, Sami Jannin, Dmitry Budker
Summary: Zero- to ultralow-field nuclear magnetic resonance is a magnetic resonance experiment that does not require strong superconducting magnets. It allows high-resolution detection of nuclear magnetism through metal and within heterogeneous media. By using dissolution dynamic nuclear polarization, signals in zero-field nuclear magnetic resonance experiments can be enhanced on sample mixtures, and this technique can be applied to a wide range of molecules. The signal enhancements can reach up to 11,000 compared to thermal prepolarization in a 2 T permanent magnet. The relaxation effects of the TEMPOL radicals used in the hyperpolarization process at zero- and ultralow-fields are also investigated to further increase the signal in future experiments.
ANALYTICAL CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
James Eills, Dmitry Budker, Silvia Cavagnero, Eduard Y. Chekmenev, Stuart J. Elliott, Sami Jannin, Anne Lesage, Joerg Matysik, Thomas Meersmann, Thomas Prisner, Jeffrey A. Reimer, Hanming Yang, Igor V. Koptyug
Summary: Magnetic resonance techniques, especially medical magnetic resonance imaging, are widely used in various scientific disciplines and practical applications. The development of spin hyperpolarization has greatly boosted both fundamental and applied magnetic resonance. Hyperpolarization techniques significantly enhance the signal intensity of magnetic resonance, overcoming its low sensitivity and opening up new possibilities for applications.
Article
Chemistry, Organic
Xi Zhao, Xiaofeng Yu, Mingjun Liu, Yanping Huo, Shaomin Ji, Xianwei Li, Qian Chen
Summary: An efficient synthesis of 9-benzylated fluorenols with high atom economy (<= 91% yield) has been achieved through an external photocatalyst-free benzylic C-H functional-ization using fluorenones under visible-light irradiation. Spectroscopic studies suggest that the photoexcited fluorenones undergo a reductive quenching with toluene derivatives to generate ketyl radicals and benzyl radicals, which then undergo a cross-coupling reaction to yield the desired fluorenols.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Applied
Bairong Liu, Yabo Chen, Qixin Liang, Yuyao Liang, Bifu Liu, Yuan Liu, Yang Gao, Qian Chen, Yanping Huo, Xianwei Li
Summary: Regiodivergent [3+2] and [4+2] C-H annulation of imines and imidate esters with unsymmetrical alkynes has been achieved under Rh(III) catalysis. Further transformation of the aldehyde and TMS functionality on the indene products is also demonstrated. The current work highlights the alcohols-directed multiple C-H annulation of imines and imidate esters, leading to diverse fused heterocycles.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Tao Yuan, Ziwei Wu, Senmao Zhai, Rong Wang, Shiwen Wu, Jiajia Cheng, Meifang Zheng, Xinchen Wang
Summary: Light-driven fixation of CO2 in organics is achieved using boron carbonitride with abundant terminal B/N defects, leading to enhanced surface active sites and charge transfer kinetics. This enables the anti-Markovnikov hydrocarboxylation of alkenes with CO2, achieving good functional group tolerance and specific regioselectivity under visible-light irradiation. Mechanistic studies demonstrate the formation of CO2 radical anion intermediate on defective boron carbonitride, enabling the anti-Markovnikov carboxylation. The utility of this method is demonstrated through gram-scale reactions, late-stage carboxylation of natural products, and synthesis of anti-diabetic GPR40 agonists.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Physics, Multidisciplinary
Rui Zhang, Dimitra Kanta, Arne Wickenbrock, Hong Guo, Dmitry Budker
Summary: We present an alignment-based 87Rb magnetometer that overcomes the issue of nonlinear Zeeman splitting in alkali-metal atomic magnetometry. The magnetometer exhibits immunity to NLZ-related errors due to a single magnetic resonance peak and well-separated hyperfine transition frequencies. Experimental results show that the magnetometer can be used for practical measurements in geomagnetic environments, achieving a photon-shot-noise-limited sensitivity of 9 fT/pat 5 mu T and remaining stable at tens of fT/ ffiffiffiffiffiffiffiffiffiffiHz p at Hz 50 mu T at room temperature.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Multidisciplinary
Xue Zhang, Abhishek Banerjee, Mahapan Leyser, Gilad Perez, Stephan Schiller, Dmitry Budker, Dionysios Antypas
Summary: The effects of scalar and pseudoscalar ultralight bosonic dark matter were investigated using quartz oscillator frequencies and atomic transitions. Linear interactions were constrained for scalar dark matter in the mass range of 1 x 10-17-8.3 x 10-13 eV, and quadratic interactions were constrained for pseudoscalar dark matter in the mass range of 5 x 10-18-4.1 x 10-13 eV. These constraints improve upon previous direct searches and astrophysical observations.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Atomic, Molecular & Chemical
Danila A. Barskiy, John W. Blanchard, Dmitry Budker, Quentin Stern, James Eills, Stuart J. Elliott, Roman Picazo-Frutos, Antoine Garcon, Sami Jannin, Igor V. Koptyug
Summary: The combination of nuclear hyperpolarization technique with (near-)zero-field modalities has great potential in various applications of nuclear magnetic resonance spectroscopy and imaging, such as biomedical diagnostics and monitoring catalytic reactions in metal reactors.
APPLIED MAGNETIC RESONANCE
(2023)
Article
Chemistry, Organic
Yupeng Zhao, Yang Gao, Zhongke Xie, Shuwei Liao, Jiebin Huang, Yanping Huo, Qian Chen, Xianwei Li, Xiao-Qiang Hu
Summary: Different chemoselectivities were observed between phenols and thiophenols in the Tf2O-promoted C3 functionalization of simple anthranils. Phenols and anthranils react to form 3-aryl anthranils via a C-C bond formation, while thiophenols form 3-thio anthranils through a C-S bond formation. Both reactions have a broad substrate scope and tolerate a wide range of functional groups, yielding the corresponding products with specific chemoselectivity.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Quantum Science & Technology
Jabir Chathanathil, Dmitry Budker, Svetlana A. Malinovskaya
Summary: A chirped-pulse quantum control scheme called C-CARS is proposed for enhancing the vibrational coherence in molecules during coherent anti-Stokes Raman scattering spectroscopy. The scheme involves chirping of the pump, Stokes, and probe pulses in the four-wave mixing process of CARS to satisfy the conditions of adiabatic passage. By utilizing the rotating wave approximation and adiabatic elimination of excited state manifold, the four-level model system is simplified into a "super-effective" two-level system. It is demonstrated that the excitation selectivity of vibrational degrees of freedom can be controlled by adjusting the spectral chirp rate of the pulses. The robustness, spectral selectivity, and adiabatic nature of this method make it advantageous for improving CARS spectroscopy for sensing, imaging, and detection purposes.
QUANTUM SCIENCE AND TECHNOLOGY
(2023)
Article
Optics
Derek F. Jackson Kimball, Dmitry Budker, Timothy E. Chupp, Andrew A. Geraci, Shimon Kolkowitz, Jaideep T. Singh, Alexander O. Sushkov
Summary: This article surveys the applications of spin-based quantum sensors in measurements probing fundamental physics. Experimental methods and technologies developed for spin-based quantum information science have rapidly advanced, enabling precise control and measurement of spin dynamics. Theories beyond the standard model predict phenomena such as discrete-symmetry-violating electromagnetic moments correlated with particle spins, exotic spin-dependent forces, and coupling of spins to ultralight bosonic dark-matter fields. Spin-based quantum sensors provide a methodology complementary to particle colliders and large-scale particle detectors, offering a way to search for these phenomena and test fundamental physics. The article also highlights areas of technological development that can enhance the sensitivity of spin-based quantum sensors to new physics.
Article
Chemistry, Multidisciplinary
James Eills, Roman Picazo-Frutos, Dudari B. B. Burueva, Larisa M. M. Kovtunova, Marc Azagra, Irene Marco-Rius, Dmitry Budker, Igor V. V. Koptyug
Summary: We demonstrate a catalyst-free approach to produce hyperpolarized [1-C-13]succinate in aqueous solutions, utilizing parahydrogen-induced polarization (PHIP) and a combination of homogeneous and heterogeneous catalytic hydrogenation reactions. A homogeneous ruthenium catalyst and para-enriched hydrogen gas are employed for PHIP to generate hyperpolarized [1-C-13]fumarate, followed by the removal of the toxic catalyst and reaction side products through a purification procedure. A second hydrogenation reaction is carried out using normal hydrogen gas and a solid Pd/Al2O3 catalyst to convert fumarate to succinate. This cost-effective method has a turnover time of a few minutes and represents a significant breakthrough for in vivo applications of hyperpolarized [1-C-13]succinate as a contrast agent.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Yuanting Huang, Jinyu Tang, Xi Zhao, Yanping Huo, Yang Gao, Xianwei Li, Qian Chen
Summary: The development of P(O)-heteroatom bond-forming reactions is crucial, but previous methods have limitations. This study presents an efficient and green photocatalytic phosphorylation of heteroatom nucleophiles utilizing acid red 51 as the photocatalyst and air as the oxidant under blue LED irradiation. The reaction exhibits broad substrate scope and provides practical access to phosphinic fluorides, phosphinic amides, phosphoramidates, and phosphinates. Mechanistic studies suggest the involvement of a phosphorus-centered radical cation generated by photocatalytic single electron transfer (SET).
Article
Astronomy & Astrophysics
I. M. Bloch, D. Budker, V. V. Flambaum, I. B. Samsonov, A. O. Sushkov, O. Tretiak
Summary: Scalar-field dark matter models suggest small oscillations of fundamental constants, which could lead to observable variations in the magnetic field of a permanent magnet. We propose an experiment using a SQUID magnetometer or a low-noise radiofrequency amplifier to detect this type of dark matter. Our results show that this experiment may have comparable sensitivity to leading experiments searching for variations of fundamental constants in a frequency range from a few Hz to about 1 MHz. We also discuss the applicability of using variations of fundamental constants to account for the interaction with scalar dark matter.
Article
Chemistry, Organic
Bairong Liu, Jianhang Rao, Weibing Liu, Yang Gao, Yanping Huo, Qian Chen, Xianwei Li
Summary: By tuning the divergent oxidative Heck reaction with O-2 enabled by self-assembled imines, olefins achieved site selectivity and stereoselectivity. The compatibility of strongly coordinating pyridines and quinolines facilitated the concise delivery of selective serotonin 4 receptor ligand, topotecan, and irinotecan analogues.
ORGANIC CHEMISTRY FRONTIERS
(2023)