Article
Chemistry, Physical
Cassandre C. Bories, Marion Barbazanges, Etienne Derat, Marc Petit
Summary: This study describes the use of silyl cobalt (III) dihydride complexes as catalysts for hydrosilylation reactions, which are efficient for a variety of imines with different protecting groups, as well as aliphatic ketimines and quinoline. Kinetic, DFT calculations, NMR spectroscopy, deuteration experiments, and X-ray diffraction analyses were used to propose a catalytic cycle based on silyl dihydrocobalt (III) complexes performing hydrocobaltation.
Article
Chemistry, Multidisciplinary
Lingling Liu, Hongli Wu, Genping Huang
Summary: Density functional theory calculations were used to investigate the nickel-catalyzed [3 + 2] cycloaddition reaction, revealing four major steps in the catalytic cycle. The enantioselectivity is mainly determined by the interaction between different groups, while the chemoselectivity can be rationalized in terms of steric effects.
CHINESE CHEMICAL LETTERS
(2021)
Article
Chemistry, Applied
Nikita V. V. Shvydkiy, Klimentiy V. V. Rimskiy, Dmitry S. S. Perekalin
Summary: The readily available cyclobutadiene platinum complex [(C4Et4)PtCl2] can catalyze the hydrosilylation of alkenes and alkynes. The reaction occurs at room temperature and does not require any solvent. The products obtained include terminal and internal alkynes, as well as terminal alkenes, with yields ranging from 43% to 99%. Various tertiary silanes (Et3SiH, (EtO)(3)SiH, Ph3SiH) and the disubstituted silane Ph2SiH2 are suitable substrates for this reaction. The hydrosilylation reaction exhibits typical anti-Markovnikov regioselectivity, yielding mainly beta(E)-vinylsilanes from alkynes and linear alkyl silanes from alkenes.
APPLIED ORGANOMETALLIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Jose Antonio Fernandez, Juan Manuel Garcia, Pablo Rios, Amor Rodriguez
Summary: The efficient catalytic hydrosilylation of ketones and aldehydes using a nickel pincer hydride complex supported by a diphosphino-boryl ligand has been studied. The presence of a boron group within the ligand skeleton enhances the catalytic activities for ketones compared to other related pincer systems. The reaction mechanism involves the initial formation of an alkoxide complex, followed by reaction with the silane to release the corresponding silyl ether and regenerate the catalyst, as supported by experimental and theoretical analysis.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Spectroscopy
Zong-Zhan Lu, Pounraj Thanasekaran, Chia-Yuan Huang, Jing-Yun Wu, Tzu-Ting Chang, Wen -Shan Li, Murugesan Velayudham, Kuang-Lieh Lu
Summary: In this study, a neutral rhenium(I)-biimidazole complex was designed and synthesized. The complex was characterized using various spectroscopic techniques and was found to have a relatively simple structure with an octahedral geometry. It showed selective recognition of fluoride ions due to its luminescent characteristics and hydrogen bonding ability.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Physical
Xiaoling Lai, Yang Li
Summary: Density functional theory calculations were used to study the mechanisms of Pd-catalyzed reactions of alkynes with tert-butyl isocyanide forming pyrroles. The calculations revealed the key steps and regioselectivity effects of this reaction.
Article
Chemistry, Multidisciplinary
Shengjie Jiang, Yanping Cai, Thayalan Rajeshkumar, Iker del Rosal, Laurent Maron, Xin Xu
Summary: This work presents the synthesis, characterization, and reactivity of the first well-defined zinc α-diazoalkyl complex. The complex reacts with a nickel catalyst to form an α-zincated phosphorus ylide, or undergoes [3+2] cycloaddition with CO2 or CO to produce a five-membered heterocyclic product. The use of CO in the cycloaddition reaction is unprecedented, demonstrating a novel CO reaction mode.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Jiaqi Su, Siwei Shu, Yinwu Li, Yong Chen, Jinxiang Dong, Yan Liu, Yanxiong Fang, Zhuofeng Ke
Summary: This study systematically compares two possible reaction mechanisms using density functional theory (DFT) to explain the difference in product selectivity in the fluorocyclization of unsaturated carboxylic acids or alcohols by hypervalent iodine (III) promoted difluoroiodotoluene. The results show that the reaction mechanism determines the selectivity, and the pKa property of the functional group on the substrate also plays a key role in the reaction mechanism.
FRONTIERS IN CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Jiahao Rao, Shicheng Dong, Chengbo Yang, Qing Liu, Xuebing Leng, Dongyang Wang, Jun Zhu, Liang Deng
Summary: Tuning the spin state of metal carbynes is a challenging task in chemistry. We have synthesized the first triplet metal terminal carbyne, which exhibits unique reactivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Polymer Science
Dalal K. Thbayh, Bela Fiser
Summary: This study compares the antioxidant potential of commonly used synthetic and natural antioxidant additives and finds that the O-H group in each additive has the highest antioxidant potential. The study also suggests that all additives have the potential to protect polymeric materials.
POLYMER DEGRADATION AND STABILITY
(2022)
Article
Green & Sustainable Science & Technology
Ruifeng Zhou, Shuyi Yang, E. Tao, Lin Liu, Jianhua Qian
Summary: Molybdenum disulfide (MoS2) with rich defectives was successfully prepared via hydrothermal method and then combined with titanium dioxide (TiO2) to enhance its catalytic performance. The material's structural stability and optimum defect degree were confirmed through various analyses. The formation of a heterojunction between MoS2 and TiO2 facilitated electron migration and separation of photogenerated electron-hole pairs. Different analytical techniques highlighted the visible light response and modulated band gap of MoS2/TiO2, as well as the presence of Z-scheme heterojunction.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Chemistry, Physical
Fabrizio Creazzo, Rangsiman Ketkaew, Kevin Sivula, Sandra Luber
Summary: An extensive understanding of the bulk crystalline structures of WO3 and WSe2, as well as the solvent effects on their surfaces, is crucial for designing efficient (photo) electrocatalysts. However, there is a lack of knowledge about the atomistic level understanding of these materials and the solvation processes on their surfaces. In this study, Density Functional Theory-based molecular dynamics simulations were used to assess the role of explicit water environment in characterizing solid surfaces. The results demonstrate the importance of considering liquid water and its dynamics in assessing catalytic features.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Inorganic & Nuclear
Man Ding, Jiarui Chang, Jia-Xue Mao, Jie Zhang, Xuenian Chen
Summary: A PNCNP pincer-ligated platinum(II) chloride complex has been synthesized and shown to be an effective catalyst for the hydrosilylation of both C=O and C=N bonds. The reactions exhibit good functional group compatibility and yield high product yields.
Article
Chemistry, Physical
Igor Fokin, Kai-Thorben Kuessner, Inke Siewert
Summary: This article introduces a method that combines organometallic catalysis and electrochemistry for the electrohydrogenation of ketones and aldehydes. Mechanistic analysis shows that by using a manganese catalyst and a proton relay, electrohydrogenation of C=O bonds can be achieved with high selectivity. The method demonstrates catalytic efficiency and high conversion rate under mild conditions.
Article
Chemistry, Organic
Yi-Fan Wang, Yu-Han He, Yan Su, Yang Ji, Rui Li
Summary: In this study, a palladium complex coordinated with a chiral SIPHOS ligand was evaluated as an efficient catalyst for asymmetric hydrosilylation reaction. The results showed that good to excellent enantioselectivities could be obtained in the hydrosilylation reaction of 1-aryl-2-silyl ethanols with selectively converted trichlorosilyl groups. Additionally, stable and high-yielding 1,2-bis(silyl) chiral compounds could be produced through the asymmetric hydrosilylation of beta-silyl styrenes followed by methylation of the trichlorosilyl group.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Gongyi Liu, Lini Zheng, Kui Tian, Haifeng Wang, Lung Wa Chung, Xumu Zhang, Xiu-Qin Dong
Summary: A highly efficient Ir/bisphosphine-thiourea catalytic system, ZhaoPhos, has been successfully developed for the asymmetric hydrogenation (AH) of challenging aryl substituted unprotected indoles, showing high reactivity and excellent stereoselective control. Various chiral indoline derivatives were obtained in good to high yields with excellent stereoselectivities. Anion-binding activation strategy played an important role in achieving both high reactivity and excellent stereoselectivity.
Article
Chemistry, Multidisciplinary
Tong-Tong Liu, Jiaxin Chen, Xin-Lei Chen, Li Ma, Bing-Tao Guan, Zhenyang Lin, Zhang-Jie Shi
Summary: A new class of boryl radicals ligated by a cyclic CAAC is reported, featuring a large spin density on the boron center as ascertained by EPR spectroscopy and DFT calculations. Structural and computational analyses revealed that stability of these radicals is assisted by the CAAC ligand and a weak but significant B(III)Br-B(II) interaction, suggesting a cooperative avenue for stabilization of boryl radicals. Two-electron reduction of these radicals provides C-H insertion products via a borylene intermediate.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Zhicheng Bao, Meirong Huang, Yan Xu, Xinhao Zhang, Yun-Dong Wu, Jianbo Wang
Summary: Bisborylalkanes are versatile bifunctional reagents in organic synthesis, with the ability to selectively convert their two boron moieties into other functional groups. This study presents a new strategy for synthesizing bisborylalkanes through the reaction of N-trisylhydrazones with diboronates, resulting in the transformation of bis(boryl) methane into 1,2-bis(boronates) through formal carbene insertion. This practical synthesis method allows for the broad substrate scope of 1,2-diboronates by readily deriving N-trisylhydrazones from corresponding aldehydes. Mechanistic studies uncover an unusual neighboring group effect of 1,1-bis(boronates) that explains the observed regioselectivity when unsymmetric 1,1-diboronates are utilized.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Zhifeng Ma, Zeyin Yan, Xin Li, Lung Wa Chung
Summary: In this study, the effects of external electric fields (EEFs) on three reactions involving hydrogen or carbon were extensively investigated. The study revealed that oriented EEFs can significantly reduce the barrier and increase the reaction rates. Furthermore, EEFs can modulate tunneling reactions and control the site selectivity of molecules with similar reactive sites.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Inorganic & Nuclear
Xin Xu, Zhenyang Lin
Summary: A mild synthetic method for transforming aromatic carbon-oxygen (C-O) bonds into useful molecules was reported. The method involved the use of a carbene complex to catalyze the asymmetric ring-opening reaction of dinaphthofuran with PhMgCl at room temperature. Density functional theory (DFT) calculations were performed to investigate the detailed mechanism, revealing a novel pathway involving Mg(II)-O coordination, phenyl nucleophile migration, and oxidative addition of a C-O bond to Ni(0). Insights into the role of the chiral NHC ligand in inducing enantioselectivity were also obtained.
Article
Chemistry, Multidisciplinary
Mingkang Zhou, Yaodong Lin, Xiao-Xuan Chen, Guangqing Xu, Lung Wa Chung, Wenjun Tang
Summary: We report the chiral diboron-templated asymmetric homocoupling of aryl alkyl ketimines, leading to the formation of chiral vicinal tetrasubstituted diamines with high enantioselectivities and good to high yields. This powerful and efficient reaction is achieved by rational design and engineering of chiral diborons, which participate in a [3,3]-sigmatropic rearrangement. DFT studies reveal that different conformational assembling strategies of chiral diborons ensure the excellent enantioselectivity in the tight concerted transition states.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Junyi Wang, Shuai Zhu, Wangyang Ma, Zhenyang Lin, Qing Ye
Summary: BN-butafulvenes, mono-BN isosteres of butafulvene and highly strained isomers of azaborines and B-amino boroles, have been synthesized via hydrolysis of the urana-borabicyclic complexes obtained from the reactions of bis(alkynyl)boranes with an uranacyclopropene complex. Their 4-dimethylaminopyridine (DMAP) adducts can further isomerize to 1,2,4,6-multisubstituted BN-9,1-naphthalenes. Both NMR reaction monitoring and theoretical calculations point to a reaction mechanism involving dearomative insertion of DMAP followed by two consecutive 1,2-hydrogen shifts. The photophysical studies of the highly substituted BN-9,1-naphthalenes reveal a notable redshift in both the UV/Vis absorption and emission spectra. The (TD)-DFT calculations corroborate the experimental data, suggesting that the strong pi-donating amino substitution at the 1- and/or 6-positions destabilizes the HOMO, and thus leading to a notable decrease of the HOMO-LUMO gap.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Rong Liang, Qinghai Zhou, Xin Li, Ming Wah Wong, Lung Wa Chung
Summary: The macrocycle effect of [2]rotaxane on the highly trans-stereoselective cyclization reaction of N-benzylfumaramide has been extensively studied. Computational results suggest that the most favorable mechanism involves deprotonation of a N-benzyl group of the fumaramide substrate by CsOH, followed by C-C bond formation and protonation by an amide functional group of the macrocycle. The trans-selective cyclization within the rotaxane is attributed to higher distortion energy caused by the twisted cis-fumaramide conformation enforced by the rotaxane.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Ke Liao, Cho Ying Chan, Siqi Liu, Xinhao Zhang, Jiean Chen, Yong Huang
Summary: Functionalizing molecules through selective cleavage of carbon-carbon bonds is a promising approach, but the selective cleavage of inert C-sp3-C-sp3 bonds in hydrocarbon feedstocks remains challenging. This article presents a straightforward protocol for cleavage and functionalization of C(sp3)-C-sp3 bonds in alkylbenzenes using photoredox catalysis. Our method utilizes two distinct bond scission pathways depending on the nature of the benzylic substituents. This strategy provides a practical means of cleaving inert C-sp3-C-sp3 bonds in molecules without heteroatoms, generating various radical species.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Masahiro Yamamoto, Wing Chun Chan, Zhenyang Lin, Makoto Yamashita
Summary: The reaction between tetra(o-tolyl)diborane(4) and organic azides yields three different compounds, diborylamines, diboryltriazenes, and B-2-hexazenes with a bicyclic B2N6 ring system. Aryl azides react to form diborylamines, while 1 equiv. of alkyl azides results in diboryltriazenes. Excess primary alkyl azide leads to the formation of new heterocyclic B-2-hexazenes. Control experiments and DFT calculations support the general reaction mechanism via diboryltriazenes to explain the formation of the B2N6 structure. The B-2-hexazenes exhibit strong fluorescence with a high fluorescent quantum yield of up to 96%.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Wenlong Sun, Chi-Ming Au, Ka-Wa Wong, Ka Lok Chan, Cheuk Kit Ngai, Hung Kay Lee, Zhenyang Lin, Wing-Yiu Yu
Summary: Directarene C-H functionalization by amidyl radicals has made significant progress for arylamides synthesis. Photocatalytic protocols can easily generate amidyl radicals under mild conditions, but designing catalysts with earth-abundant Fe complexes for C-H amidation is an attractive approach for controlling selectivity. However, the preference for high-spin configuration makes it challenging to design robust Fe catalysts for C-H amidation.
Article
Chemistry, Multidisciplinary
Xin Chang, Xue-Tao Liu, Fangfang Li, Yuhong Yang, Lung Wa Chung, Chun-Jiang Wang
Summary: A series of benzofulvenes without electron-withdrawing substituents were used as 2π-type dipolarophiles in Cu(i)-catalyzed asymmetric 1,3-dipolar cycloaddition reactions. The non-benzenoid aromatic characteristic of benzofulvenes served as a key driving force for their activation. The methodology allowed for the synthesis of multi-substituted chiral spiro-pyrrolidine derivatives with exclusive chemo-/regioselectivity and high to excellent stereoselectivity.
Article
Chemistry, Physical
Yongheng Jia, Ruichen Li, Yang Zhou, Shenghe Zhao, Hui Yu, Jianpu Wang, Zhenyang Lin, Haibin Su, Ni Zhao
Summary: Perovskite light-emitting diodes (PeLEDs) based on 3D mixed Br-Cl compositions exhibit good color stability and efficiency in the sky-blue range, but suffer from a significant performance decay in the deep-blue emission. This decay is mainly attributed to the poor morphology of the emissive layer. By combining theoretical and experimental approaches, it is discovered that the exchange of halide ions in lead complexes drives the precipitation of CsCl, resulting in low solubility at high Cl/Br ratios and inadequate perovskite film coverage. A metastable dissolution strategy is proposed, leading to deep-blue PeLEDs with a record high EQE of 4% and excellent spectral stability.
Article
Chemistry, Multidisciplinary
Zhongming Cheng, Tilong Yang, Can Li, Yunshun Deng, Fangjia Zhang, Pinhong Chen, Zhenyang Lin, Shengming Ma, Guosheng Liu
Summary: This study presents a copper-catalyzed radical relay strategy for the site-selective cyanation of sp(2) C-H bonds in allenes. The reactions show broad substrate scope and remarkable functional group compatibility under mild conditions. The site-selectivity is attributed to the unique pocket created by the Cu-bound nitrogen-centered radical and the crucial hydrogen bonding between the fluoride and the hydrogen atom. Late-stage functionalization of drug-like bioactive molecules containing an allene motif becomes feasible.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Jiao Jiao, Pei He, Tilong Yang, Tingwei Zhang, Linghua Wang, Tian Han, Yong Nie, Zhenyang Lin, Pengfei Li
Summary: An asymmetric synthesis of chiral metallacarboranes using a traceless chiral N-tertbutylsulfinamide auxiliary is reported. Investigations reveal a stereospecific SN2-type reaction mechanism, providing a new pathway for the preparation of chiral metallacarboranes and related compounds.
ORGANIC CHEMISTRY FRONTIERS
(2023)
