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In view of the problems such as large works of manual preparation of LKJ basic source data and excessive dependence on personal ability of data compilers, this paper proposes a LKJ data preparation technology based on technical data of train diagram, and a set of LKJ data preparation system is developed based on this technology. The system realizes intelligent identification of technical data of train diagram adopting Excel, and realizes transformation of technical data of train diagram into standard engineering data, then converts the engineering data into LKJ basic source data. It builds engineering database and realizes LKJ basic data management and preparation. Based on the engineering data of main line annunciator and station annunciator, it realizes automatic preparation of line frame data such as station, track and annunciator zoning, and realizes automatic preparation of display data such as slope, bend, bridge and tunnel according to the starting and ending mileage and line information of zoning. In order to facilitate the upgrading of LKJ basic source data, the system realizes the comparison and automatic update between LKJ basic source data and engineering data. The field test shows that it can realize automatic production of nearly 90% LKJ basic source data by this technology, which can effectively improve the production efficiency of data and reduce the intensity of data preparation.

Controlling the cross‐coupling reaction between two different radicals is a long‐standing challenge due to the process occurring statistically, which would lead to three products, including two homocoupling products and one cross‐coupling product. Generally, the cross‐coupling selectivity is achieved by the persistent radical effect (PRE) that requires the presence of a persistent radical and a transient radical, thus resulting in limited radical precursors. In this paper, a highly selective cross‐coupling of alkyl radicals with acyl radicals to construct C(sp2)−C(sp3) bonds, or with alkyl radicals to construct C(sp3)−C(sp3) bonds have been achieved with the readily available carboxylic acids and their derivatives (NHPI ester) as coupling partners. The success originates from the use of tridentate ligand (2,2′ : 6′,2′′‐terpyridine) to enable radical cross‐coupling process to Ni‐mediated organometallic mechanism. This protocol offers a facile and flexible access to structurally diverse ketones (up to 90 % yield), and also a new solution for the challenging double decarboxylative C(sp3)−C(sp3) coupling. The broad utility and functional group tolerance are further illustrated by the late‐stage functionalization of natural‐occurring carboxylic acids and drugs. [ABSTRACT FROM AUTHOR]

α‐Trifluoromethyl alkenes are versatile CF3‐containing feedstocks. They have been widely used to construct gem‐difluoroalkene scaffolds through β−F elimination. The application of α−CF3 alkenes as trifluoromethylating reagents has been less explored. Herein, we report an efficient route for the synthesis of β‐trifluoromethylated ketones from readily accessed α−CF3 styrenes and aromatic carboxylic acids under photoredox catalysis. The reactions proceed by phosphoranyl radical promoted deoxygenation of aromatic acids, generating acyl radicals for subsequent hydroacylation of α−CF3 styrenes. The valuable trifluoromethyl‐containing compounds could be produced in good yields under mild conditions. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: In this paper, we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines. The protocol is performed at mild conditions without the use of noble metals as catalysts. A wide range of structurally diverse secondary amines could be obtained in good yields (up to 94%) with good functional group tolerance. This transformation shows good to excellent selectivity, avoiding the generation of over alkylated byproducts. [ABSTRACT FROM AUTHOR]

The alkyne unit is a versatile building block in organic synthesis and the development of selective multifunctionalization of alkynes is an important object of research in this field. Herein, we report an interesting gold-catalyzed, four-component reaction that achieves the oxo-arylfluorination or oxo-arylalkenylation of internal aromatic or aliphatic alkynes, efficiently breaking a carbon-carbon triple bond and forming four new chemical bonds. The reaction divergence can be controlled by site-directing functional groups in the alkynes; the presence of a phosphonate unit favors the oxo-arylfluorination, while the carboxylate motif benefits oxo-arylalkenylation. This reaction is enabled by an Au(I)/Au(III) redox coupling process using Selectfluor as both an oxidant and a fluorinating reagent. A wide range of structurally diverse α,α-disubstituted ketones, and tri- or tetra-substituted unsaturated ketones have been prepared in synthetically valuable yields and with excellent chemo-, regio- and stereoselectivity. The gram-scale preparation and late-stage application of complex alkynes have further enhanced their synthetic value. The development of selective multifunctionalization of alkynes is essential for organic synthesis with alkyne units as building blocks. Here the authors report a gold-catalyzed, four-component reaction that achieves the oxo-arylfluorination or oxo-arylalkenylation of internal aromatic or aliphatic alkynes [ABSTRACT FROM AUTHOR]

Selective deuteration of unactivated C(sp3)-H bonds is a highly attractive but challenging subject of research in pharmaceutical chemistry, material science and synthetic chemistry. Reported herein is a practical, highly selective and economical efficient hydrogen/deuterium (H/D) exchange of unactivated C(sp3)-H bonds by synergistic photocatalysis and hydrogen atom transfer (HAT) catalysis. With the easily prepared PMP-substituted amides as nitrogen-centered radical precursors, a wide range of structurally diverse amides can undergo predictable radical H/D exchange smoothly with inexpensive D2O as the sole deuterium source, giving rise to the distal tertiary, secondary and primary C(sp3)-H bonds selectively deuterated products in yields of up to 99% and excellent D-incorporations. In addition to precise monodeuteration, this strategy can also achieve multideuteration of the substrates contain more than one remote C(sp3)-H bond, which opens a method to address multi-functionalization of distal unactivated C(sp3)–H bonds. Deuteration of unactivated C(sp3)̵̵̵̵̵̵̵̵–H bonds is a simple route to deuterated compounds, of use in pharmaceutical chemistry, material science, and synthetic chemistry. Here, the authors describe a hydrogen/deuterium (H/D) exchange of remote unactivated C(sp3)̵̵̵̵̵̵̵̵–H bonds via photocatalysis, proceeding through hydrogen atom transfer. [ABSTRACT FROM AUTHOR]

Aromatic tertiary amines are one of the most important classes of organic compounds in organic chemistry and drug discovery. It is difficult to efficiently construct tertiary amines from primary amines via classical nucleophilic substitution due to consecutive overalkylation. In this paper, we have developed a radical tandem C-N coupling strategy to efficiently construct aromatic tertiary amines from commercially available carboxylic acids and nitroarenes. A variety of aromatic tertiary amines can be furnished in good yields (up to 98%) with excellent functional group compatibility under mild reaction conditions. The use of two different carboxylic acids also allows for the concise synthesis of nonsymmetric aromatic tertiary amines in satisfactory yields. Mechanistic studies suggest the intermediacy of the arylamine–(TPP)Fe(III) species and might provide a possible evidence for an SH2 (bimolecular homolytic substitution) pathway in the critical C-N bond formation step. Aromatic tertiary amines are versatile building blocks in organic synthesis. In this article, the authors report on an iron-catalysed reaction for the decarboxylative C-N coupling from carboxylic acids and nitroarenes, leading to non-symmetric tertiary aromatic amines. [ABSTRACT FROM AUTHOR]

We report a general, practical and scalable hydroacylation reaction of ethylene with aromatic carboxylic acids with the synergistic combination of nickel and photoredox catalysis. Under ambient temperature and pressure, feedstock chemicals such as ethylene can be converted into high-value-added aromatic ketones in moderate to good yields (up to 92%) with reaction time of 2 – 6 hours. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: In this paper, we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines. The protocol is performed at mild conditions without the use of noble metals as catalysts. A wide range of structurally diverse secondary amines could be obtained in good yields (up to 94%) with good functional group tolerance. This transformation shows good to excellent selectivity, avoiding the generation of over alkylated byproducts. [ABSTRACT FROM AUTHOR]

Controlling the cross-coupling reaction between two different radicals is a long-standing challenge due to the process occurring statistically, which would lead to three products, including two homocoupling products and one cross-coupling product. Generally, the cross-coupling selectivity is achieved by the persistent radical effect (PRE) that requires the presence of a persistent radical and a transient radical, thus resulting in limited radical precursors. In this paper, a highly selective cross-coupling of alkyl radicals with acyl radicals to construct C(sp 2 )-C(sp 3 ) bonds, or with alkyl radicals to construct C(sp 3 )-C(sp 3 ) bonds have been achieved with the readily available carboxylic acids and their derivatives (NHPI ester) as coupling partners. The success originates from the use of tridentate ligand (2,2' : 6',2''-terpyridine) to enable radical cross-coupling process to Ni-mediated organometallic mechanism. This protocol offers a facile and flexible access to structurally diverse ketones (up to 90 % yield), and also a new solution for the challenging double decarboxylative C(sp 3 )-C(sp 3 ) coupling. The broad utility and functional group tolerance are further illustrated by the late-stage functionalization of natural-occurring carboxylic acids and drugs., (© 2024 Wiley-VCH GmbH.)

Selective activation of the benzylic C(sp 3 )-H bond is pivotal for the construction of complex organic frameworks. Achieving precise selectivity among C-H bonds with comparable energetic and steric profiles remains a profound synthetic challenge. Herein, we unveil a site- and stereoselective benzylic C(sp 3 )-H alkenylation utilizing metallaphotoredox catalysis. Various linear and cyclic ( Z )-all-carbon tri- and tetrasubstituted olefins can be smoothly obtained. This strategy can be applied to complex substrates with multiple benzylic sites, previously deemed unsuitable due to the uncontrollable site-selectivity. In addition, sensitive functional groups such as terminal alkenyl and TMS groups are compatible under the mild conditions. The exceptional site-selectivity and broad substrate compatibility are attributed to the visible-light catalyzed relay electron transfer-proton transfer process. More importantly, we have extended this methodology to achieve enantioselective benzylic C(sp 3 )-H alkenylation, producing highly enantioenriched products. The applicability and scalability of our protocol are further validated through late-stage functionalization of complex structures and gram-scale operations, underscoring its practicality and robustness., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The involvement of manganese radical for halogen atom transfer (XAT) reactions has been esteemed as one reliable method but encountered with limited catalytic models. In this paper, a novel bimetallic relay catalysis of Mn 2 (CO) 10 and cobaloxime has been developed for divergent dehydrogenative difluoroalkylation of alkenes using commercially available difluoroalkyl bromides. A wide range of structurally diverse terminal, cyclic and internal alkenes as well as tetrasubstituted alkenes are found to be good coupling partners to deliver difluoroalkylated allylic products and difluoromethylated cyclic products, accompanied with the production of H 2 as the by-product. This bimetallic relay strategy features broad substrate scope, mild reaction conditions and excellent functional group compatibility. Its success represents an important step-forward to expedite the construction of a rich library of difluoroalkylated products., (© 2023 Wiley-VCH GmbH.)

Activated alkyl halides have been extensively explored to generate alkyl radicals with Ru- and Ir- photocatalysts for 1,2-difunctionalization of alkenes, but unactivated alkyl bromides remain challenging substrates due to their strong reduction potential. Here we report a three-component 1,2-difunctionalization reaction of alkenes, unactivated alkyl bromides and nucleophiles (e.g., amines and indoles) using a trinuclear gold catalyst [Au 3 (tppm) 2 ](OTf) 3 . It can achieve the 1,2-aminoalkylation and 1,2-alkylarylation readily. This protocol has a broad reaction scope and excellent functional group compatibility (>100 examples with up to 96 % yield). It also affords a robust formal [2+2+1] cyclization strategy for the concise construction of pyrrolidine skeletons under mild reaction conditions. Mechanistic studies support an inner-sphere single electron transfer pathway for the successful cleavage of inert C-Br bonds., (© 2023 Wiley-VCH Verlag GmbH.)

Herein, we present a manganese-catalyzed, branched-selective hydroalkenylation of terminal alkynes, under mild conditions through facile installation of a versatile silanol as a removable directing group. With an alkenyl boronic acid as the coupling partner, this reaction produces stereodefined (E,E)-1,3-dienes with high regio-, chemo- and stereoselectivity. The protocol features mild reaction conditions such as room temperature and an air atmosphere, while maintaining excellent functional group compatibility. The resulting 1,3-dienesilanol products serve as versatile building blocks, as the removal of the silanol group allows for the synthesis of both branched terminal 1,3-dienes for downstream coupling reactions, as well as stereoselective construction of linear (E,E)-1,3-dienes and (E,E,E)- or (E,E,Z)-1,3,5-trienes. In addition, a Diels-Alder cycloaddition can smoothly and selectively deliver silicon-containing pentasubstituted cyclohexene derivatives. Mechanistic investigations, in conjunction with DFT calculations, suggest a bimetallic synergistic activation model to account for the observed enhanced catalytic efficiency and good regioselectivity., (© 2023 Wiley-VCH GmbH.)

Exploration of elementary reactions in organometallic catalysis is an important method with which to discover new reactions. In this article, we report a gold(I)-catalyzed iodo-alkynylation of benzyne involving the merging of challenging migratory insertion and an oxidative addition process in gold catalytic cycle. A wide range of structurally diverse alkynyl iodides are good coupling partners in this iodo-alkynylation transformation. Both aliphatic and aromatic alkynyl iodides can react with benzynes smoothly to afford highly functionalized 1,2-disubstituted aromatics in moderate to good yields. Its good functional group compatibility and late-stage application of complex molecules demonstrate its synthetic robustness. Studies of the mechanism reveals the feasibility of oxidative addition and the DFT calculations demonstrate the possible migratory insertion of benzyne into Au III -carbon bonds in the Au I /Au III redox catalytic cycle, representing an important step towards an elementary reaction in gold chemistry research., (© 2023 Wiley-VCH GmbH.)

We report a thioacylation transfer reaction based on nickel-catalyzed C-C bond cleavage of thioesters with sp 2 -hybridized electrophiles. Aryl bromides, iodides, and alkenyl triflates can participate in thioester transfer reaction of aryl thioesters, affording a wide range of structurally diverse new thioesters in yields of up to 98% under mild reaction conditions. With this protocol, it is possible to construct alkenyl thioesters from the corresponding ketones through the generation of alkenyl triflates.