Article
Chemistry, Physical
Xiao-Yan Qin, Fan-Tao Meng, Mian Wang, Shu-Jiang Tu, Wen-Juan Hao, Jianyi Wang, Bo Jiang
Summary: Transition metal-catalyzed skeletal rearrangement reactions have rapidly advanced in the organic community, providing versatile methods for selective synthesis of special molecular scaffolds. A gold-catalyzed skeletal rearrangement of alkenes with alkynyl bromides was reported in this study, allowing for the regioselective generation of diverse tricyclic heterocycles with good yields. Mechanistic investigations using theoretical calculations were conducted to explain the regioselectivity of the reaction.
Article
Chemistry, Organic
Xiaoping Xue, Biqiong Hong, Jia Feng, Zhenhua Gu
Summary: An Oxone-mediated oxidative ring-opening reaction was reported for the synthesis of 2-hydroxy-2'-aroyl-1,1'-biaryls by cleaving a carbon-carbon bond of 4,5-disubstituted 9H-fluoren-9-ols. The reaction can be efficiently carried out by heating a mixture of fluoren-9-ols, Oxone, and 1,1,1,3,3,3-hexafluoroisopropanol at 60 degrees C for 4 hours. The proposed persulfate-involved ring-expansion processes were supported by DFT calculations.
Article
Chemistry, Multidisciplinary
Xiaoming Jie, Chaohuang Chen, Constantin G. Daniliuc, Gerald Kehr, Gerhard Erker
Summary: The hydroboration of styrene or vinylcyclohexane with the IMes(C6F5)BH+ cation followed by deprotonation provides a convenient synthetic route to boraalkenes [B]=CHCH2R. The in-situ generated IMes(SCN)BH+ system reacts similarly with 1,1-diphenylethene, resulting in the formation of isothiocyanato-substituted boraalkene. The boraalkenes participate in [2+2] cycloaddition reactions with heterocumulenes, yielding respective four-membered heterocycles. The addition of borane HB(C6F5)(2) to [B]=CHCH2R+CO2 cycloadducts leads to cleavage of the central B-C sigma-bond.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Andrey V. Protchenko, M. Angeles Fuentes, Jamie Hicks, Caitilin McManus, Remi Tirfoin, Simon Aldridge
Summary: The reaction of boryl-substituted stannylene with carbon dioxide proceeds via pathways involving insertion into the Sn-B bonds. Several different products can be derived from this reaction, including boryl(borylcarboxylate)ester and bis(borylcarboxylate) stannylene complexes. The possibility of extrusion of CO from the reaction products to generate boryloxy systems has also been observed.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Physical
R. Behjatmanesh-Ardakani, P. Nazari
Summary: This study investigates the adsorption and dissociation of tetrachlorodibenzofuran on different carbon nanotubes and finds that co-adsorbed, defected, and Al-doped carbon nanotubes are effective catalysts for the first step dissociation of TCDF.
APPLIED SURFACE SCIENCE
(2022)
Review
Environmental Sciences
Christoph Ruecker, Elisa Grabitz, Klaus Kuemmerer
Summary: Methylsiloxanes, compounds containing H3C-Si-O subunits, are pervasive environmental pollutants created through industrial production and widely used. Whether and to what extent microorganisms can degrade these compounds remains uncertain. This review critically examines existing evidence for and against microbial degradation of methylsiloxanes, particularly the cleavage of Si-CH3 bonds, finding no convincing proof of cleavage by native environmental microorganisms.
Article
Multidisciplinary Sciences
Qinglei Meng, Jiang Yan, Ruizhi Wu, Huizhen Liu, Yang Sun, Ningning Wu, Junfeng Xiang, Lirong Zheng, Jing Zhang, Buxing Han
Summary: Efficient production of benzene from lignin is of great importance but has not been realized. In this study, a strategy is developed to transform lignin into benzene over RuW/zeolite catalyst in water, with a high yield of 18.8% on lignin weight basis. This high-performance protocol paves the way for efficiently producing benzene using lignin as the feedstock.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Huaiyuan Zhu, Arseni Kostenko, Daniel Franz, Franziska Hanusch, Shigeyoshi Inoue
Summary: A novel nontransient acyclic iminosilylene compound with a bulky super silyl group and a methylated backbone was isolated. This compound shows intermolecular Bu''chner-ring-expansion-type reactivity, forming silicon analogs of cycloheptatrienes. The reactions with N-heteroarenes are faster and irreversible, resulting in azasilepins with nearly planar seven-membered rings.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Helene Beucher, Johannes Schoergenhumer, Estibaliz Merino, Cristina Nevado
Summary: A chelation-assisted oxidative addition of gold(I) into the C-C bond of biphenylene was achieved in this study. The presence of coordinating groups played a crucial role in the successful activation of strained C-C bonds by gold. This research provides a new and straightforward method for synthesizing cyclometalated gold(III) complexes.
Article
Multidisciplinary Sciences
Can Yang, Xiaoyu Zhou, Lixing Shen, Zhuofeng Ke, Huanfeng Jiang, Wei Zeng
Summary: The authors developed a Mn(I)-catalyzed sigmatropic rearrangement of beta, gamma-unsaturated alcohols via C-C sigma bond activation. This rearrangement allows for selective reorganization of carbon skeletons, providing a strategy for the synthesis of complex structures with high atom and step economy.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Liuzhou Gao, Xueting Liu, Guoao Li, Shengda Chen, Jia Cao, Guoqiang Wang, Shuhua Li
Summary: A metal-free silyl-pyridylation method for the synthesis of C-4-silylalkylated pyridines has been demonstrated. This method proceeds through a silyl radical addition/radical-radical coupling sequence and exhibits a broad substrate scope and excellent functional group compatibility, making it suitable for late-stage modification of bioactive molecules.
Article
Chemistry, Inorganic & Nuclear
Joseph A. Zurakowski, Kasey R. Brown, Marcus W. Drover
Summary: Diphosphines play a dominant role as supporting ligands in transition-metal chemistry. In this study, complexes of the type [Cp*Fe(diphosphine)(X)] (X = Cl, H) were described, where a Lewis-acidic secondary coordination sphere (SCS) was installed via allyl group hydroboration using dicyclohexylborane (HBCy2) for diphosphine = 1,2-bis(di-allylphosphino)ethane (tape). The resulting chloride complex, [Cp*Fe(P2BCy4)(Cl)], displayed cyclometalation at iron upon treatment with n-butyllithium.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Dayong Sang, Bingqian Dong, Yunfeng Liu, Juan Tian
Summary: The chemoselective cleavage of C-N bonds of amides, sulfonamides, and acylsulfonamides can be achieved using aluminum halides. AlCl3 and AlI3 display complementary reactivities towards different alkyl and acyl moieties.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Kevin Breitwieser, Fabian Dankert, Annette Gruenwald, Paula R. Mayer, Frank W. Heinemann, Dominik Munz
Summary: This study reports C-C insertion reactions of a 12-electron palladium(0) surrogate stabilized by a cyclic(alkyl)(amino) carbene (CAAC) ligand. The reactions proceed quantitatively at or below room temperature, outlining perspectives for C-C bond functionalization catalysis.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Kevin Breitwieser, Fabian Dankert, Annette Gruenwald, Paula R. Mayer, Frank W. Heinemann, Dominik Munz
Summary: This study reports on C-C insertion reactions of a 12-electron palladium(0) surrogate stabilized by a cyclic(alkyl)(amino) carbene (CAAC) ligand. Substrates including benzonitrile, biphenylene, benzocyclobutenone, and naphtho[b]cyclopropene were studied to elucidate the effect of ring strain and hybridization on the reactions. All reactions proceed quantitatively at or below room temperature, outlining perspectives for mild C-C bond functionalization catalysis.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Lei Jiang, Yinran Wang, Hanyang Sun, Tingting Fu, Zhaomin Hou, Fang Guo
Summary: This study successfully achieved the coordination polymerization of diphenylphosphinostyrene and its copolymerization with styrene, resulting in a new series of phosphine functionalized syndiotactic polystyrene with excellent thermal stability and chemical resistance. The combination of triphenylphosphine and syndiotactic polystyrene allowed for the stable immobilization of metal nanoparticles to form highly robust nanocatalysts, showing high efficiency as a heterogeneous catalyst for the synthesis of quinoline derivatives.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Polymer Science
Fen You, Xiaohui Kang, Masayoshi Nishiura, Jingjing Zhai, Suting Xu, Jixing Wang, Xiaochao Shi, Zhaomin Hou
Summary: This study reports the living and highly 3,4-isoselective polymerization of biobased monomer beta-farnesene using a phosphine-functionalized fluorenyl-ligated yttrium catalytic system. The coordination of the phosphine group plays a pivotal role in the regio- and stereoselectivity of the polymerization. Block copolymers with specific properties were successfully prepared. This research is important for reducing petrochemical dependency.
Article
Chemistry, Multidisciplinary
Haobing Wang, Yang Yang, Masayoshi Nishiura, You-lee Hong, Yusuke Nishiyama, Yuji Higaki, Zhaomin Hou
Summary: The synthesis of self-healing polymers from simple commodity dienes, such as isoprene, using catalyst-controlled polymerization has shown to produce excellent self-healing elastomers. The self-healability is attributed to nanoscale heterogeneities formed by microphase separation of hard 3,4-segments from a flexible cis-1,4-segment matrix.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Wenxuan Xu, Xuefeng Cong, Kun An, Shao-Jie Lou, Zhenghua Li, Masayoshi Nishiura, Tetsuro Murahashi, Zhaomin Hou
Summary: In this study, the intermolecular regio- and diastereoselective formal [2+2] cycloaddition of allenes with amino-functionalized alkenes was achieved using half-sandwich rare-earth catalysts. The reaction proceeded through an allene C(sp(2))-H activation mechanism, leading to the synthesis of a new family of cyclobutane and cyclobutene derivatives.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Masanori Takimoto, Mingyu Liu, Masayoshi Nishiura, Zhaomin Hou
Summary: A regioselective benzylic C-H alumination method has been developed for various symmetrical and nonsymmetrical 2,6-alkylpyridines. The resulting alkylaluminum species can be transformed to the corresponding alcohols by oxidation. Additionally, Cu-catalyzed allylation and benzylation reactions, as well as Pd-catalyzed arylation reactions, can be applied to the alkylaluminum species to obtain α-mono-allylated, α-mono-benzylated, and α-mono-arylated 2-alkylpyridine derivatives.
Article
Chemistry, Physical
Aniket Mishra, Ping Wu, Xuefeng Cong, Masayoshi Nishiura, Gen Luo, Zhaomin Hou
Summary: This study reports the exo-selective, regiospecific annulation of a wide range of functionalized aromatic substrates with 1,1-disubstituted alkenes through C(sp2)-H and benzylic C(sp3)-H activation by half-sandwich rare-earth catalysts. It provides a straightforward and atom-efficient method for the synthesis of indane and tetralin derivatives bearing an all-carbon quaternary stereocenter that were previously difficult to access by other catalysts. The reaction mechanism has been elucidated using deuterium-labeling experiments and DFT calculations.
Review
Chemistry, Multidisciplinary
Qingde Zhuo, Xiaoxi Zhou, Takanori Shima, Zhaomin Hou
Summary: This review focuses on N-2 activation and addition to unsaturated substrates mediated by transition metal complexes, which resulted in various N-C bond formation products. The emphasis is on the reaction modes and mechanisms. It is hoped that this work will inspire further explorations in this challenging field.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Xuefeng Cong, Lin Huang, Zhaomin Hou
Summary: This Perspective focuses on recent advances in C-H functionalization with alkenes, allenes, and alkynes by half-sandwich rare-earth catalysts, including asymmetric transformations. The reaction generally proceeds through formal C-H addition to unsaturated C-C bonds, thus constituting a 100% atom-efficient route for the construction of new C-C bonds. Future outlooks in related areas are also described.
Article
Chemistry, Multidisciplinary
Aniket Mishra, Xuefeng Cong, Masayoshi Nishiura, Zhaomin Hou
Summary: Multisubstituted chiral 1-aminoindanes are important components in pharmaceuticals and bioactive molecules. The synthesis of chiral 1-aminoindanes is of great interest and importance, and the asymmetric[3 + 2] annulation of aldimines with alkenes through C-H activation is a promising method. This study reports the enantioselective [3 + 2] annulation of aromatic aldimines and alkenes via ortho-C(sp(2))-H activation using chiral half-sandwich scandium catalysts, which provides a straightforward route for the synthesis of multisubstituted chiral 1-aminoindanes.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yat-Ming So, Ching Tat To, Murali Mohan Guru, Takanori Shima, Zhaomin Hou
Summary: Carbon-carbon bond formation via coupling of two organic components is an important chemical transformation. In this study, a hydrodeoxygenative coupling of aromatic aldehydes was achieved to form bibenzyls by a titanium imide/hydride complex. The complex also demonstrated the ability to activate and functionalize N-2, as well as providing a platform for C-C bond formation using carbonyl compounds.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Masanori Takimoto, Zhaomin Hou
Summary: An efficient protocol for the carbozincation of allenamides has been developed using dialkylzinc reagents catalyzed by an NHC Cu complex. This method allows for regio- and stereoselective introduction of alkyl and zinc groups to the allenamides, leading to the formation of alkenylzinc species. These species can further undergo C-C bond-forming reactions, resulting in the synthesis of multi-substituted enamides.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Aniket Mishra, Ping Wu, Xuefeng Cong, Masayoshi Nishiura, Gen Luo, Zhaomin Hou
Summary: In this study, we report the exo-selective, regiospecific annulation of a wide range of functionalized aromatic substrates with 1,1-disubstituted alkenes through C(sp(2))-H and benzylic C(sp(3))-H activation using half-sandwich rare-earth catalysts. This protocol provides a straightforward and atom-efficient route for synthesizing indane and tetralin derivatives bearing an all-carbon quaternary stereocenter that were previously difficult to access using other catalysts. The reaction mechanism has been elucidated through deuterium-labeling experiments and DFT calculations.
Article
Chemistry, Inorganic & Nuclear
Jiayu Zhang, Wenshuang Huang, Kailing Han, Guoyong Song, Shaowei Hu
Summary: A series of first-row early transition metal dialkyl complexes bearing pincer ligands have been synthesized and their activities in styrene polymerization have been explored.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Wei Zhou, Xuefeng Cong, Masayoshi Nishiura, Zhaomin Hou
Summary: The ortho-selective benzylic C(sp(3))-H alkenylation of 2-methyl tertiary anilines with internal alkynes has been achieved for the first time by using a half-sandwich scandium catalyst. This protocol provides a straightforward route for the synthesis of a new family of 2-allylaniline derivatives, featuring broad substrate scope, 100% atom-efficiency, high yields, and high chemo-, regio-, and stereoselectivity.
CHEMICAL COMMUNICATIONS
(2022)