Methane Activation by (MoO3)5O- Cluster Anions: The Importance of Orbital Orientation
This study not only makes up the blank of thermal methane activation by the O b •- radical on negatively charged clusters but also yields new insights into methane activation by the atomic oxygen radical anions.PMID:34672031 | DOI:10.1002/chem.202103321 (Source: Chemistry)
Source: Chemistry - October 21, 2021 Category: Chemistry Authors: Man Ruan Yan-Xia Zhao Mei-Qi Zhang Sheng-Gui He Source Type: research

Late-stage amination of drug-like benzoic acids: Access to anilines and drug conjugates via directed iridium-catalyzed C-H activation
Chemistry. 2021 Oct 21. doi: 10.1002/chem.202103510. Online ahead of print.ABSTRACTFunctionalization of C-H bonds, ubiquitous in drugs and drug-like molecules, represents an important synthetic strategy with a potential to streamline the drug discovery process. Late-stage aromatic C-N bond forming reactions are highly desirable, but despite their significance, accessing aminated analogues through direct and selective amination of C-H bonds remains a challenging goal. The herein presented method enables the amination of a wide array of benzoic acids with high selectivity. The robustness of the system is manifested by the la...
Source: Chemistry - October 21, 2021 Category: Chemistry Authors: Bel én Martín-Matute Erik Weis Magnus J Johansson Source Type: research

Multiple regulation effects of ammonium acetate on ZnO growth process in chemical bath deposition
This study contributes to understand the roles of ammonium acetate on the growth mechanism of ZnO in Zn(NO 3 ) 2 -HMTA system. The growth process indicates that the nucleation experienced Zn 2+ -layered basic zinc salta(LBZs)-ZnO process, while the self-assembled unit changed from urchin-shaped, rod-shaped to a fully coupled twin-shaped structure with increasing ammonium acetate concentration. Ammonium acetate dominates the growth process by combing the ligand-ligand interaction of acetate ions binding to the same Zn-rich (0001) polar surface and ammonium ions regulating hexamethylenetetramine (HMTA) hydrolysis. Relatively...
Source: Chemistry - October 21, 2021 Category: Chemistry Authors: Gen Liu Xue Yu Rui Xu Xiaodong Zhu Yanqing Ma Lei Ma Source Type: research

Cooperative Effects in Heterometallic Complexes
Chemistry. 2021 Oct 21. doi: 10.1002/chem.202103666. Online ahead of print.NO ABSTRACTPMID:34672037 | DOI:10.1002/chem.202103666 (Source: Chemistry)
Source: Chemistry - October 21, 2021 Category: Chemistry Authors: Marc H Prosenc Manfred M Kappes Gereon Niedner-Schatteburg Source Type: research

Photocatalytic Activity of Supported Metal Nanoparticles and Single Atoms
Chemistry. 2021 Oct 20. doi: 10.1002/chem.202102877. Online ahead of print.ABSTRACTPhotocatalysis has been known as one of the promising technologies due to its eco-friendly nature. However, the potential application of many photocatalysts is limited owing to their large bandgaps and inefficient use of the solar spectrum. One strategy to overcome this problem is to combine the advantages of heteroatom-containing supports with active metal centres to accurately adjust the structural parameters. Metal nanoparticles (MNPs) and single atom catalysts (SACs) are excellent candidates due to their distinctive coordination environm...
Source: Chemistry - October 21, 2021 Category: Chemistry Authors: Mahnaz Najafi Sara Abednatanzi Abbas Yousefi Mehrorang Ghaedi Source Type: research

Rh(I)/(III)-N-Heterocyclic Carbene Complexes: Effect of Steric Confinement Upon Immobilization on Regio- and Stereoselectivity in the Hydrosilylation of Alkynes
Chemistry. 2021 Oct 21. doi: 10.1002/chem.202103099. Online ahead of print.ABSTRACTRh(I) NHC and Rh(III) Cp* NHC complexes (Cp* = pentamethylcyclopentadienyl, NHC = N -heterocyclic carbene = pyrid-2-ylimidazol-2-ylidene (Py-Im), thiophen-2-ylimidazol-2-ylidene) are presented. Selected catalysts were selectively immobilized inside the mesopores of SBA-15 having average pore diameters of 5.0 and 6.2 nm, respectively. Together with their homogenous progenitors, the immobilized catalysts were used in the hydrosilylation of terminal alkynes. For aromatic alkynes, both the neutral and cationic Rh(I) complexes showed excellent re...
Source: Chemistry - October 21, 2021 Category: Chemistry Authors: Pradeep K R Panyam Boshra Atwi Felix Ziegler Wolfgang Frey Michal Nowakowski Matthias Bauer Michael Rudolf Buchmeiser Source Type: research

Tetra metallic Copper Complex to Nanoscale Copper: Selective and Switchable Dehydrogenation-Hydrogenation under light
Chemistry. 2021 Oct 21. doi: 10.1002/chem.202103383. Online ahead of print.ABSTRACTDiscrete photoactive ultrafine nanocluster of copper with less than hundreds of atoms comprising stimuli-responsive switchable redox-active states is highly desired to control two different antagonistic reactions. Herein, we disclosed mixed-valent tetra metallic copper complex ( C-1 ) of N-O-N Schiff base ligand, in which its five different Cu-Cu interaction was utilized for the generation of photoactive nanoscale copper [LCu(0) n , S-1 ] via the reduction of coordinated imine to the amine of C-1 . The presence of ligand providing stability ...
Source: Chemistry - October 21, 2021 Category: Chemistry Authors: Sanjay Pratihar Kasturi Sarmah Amishwar Raysing Shelte Ankur K Guha Source Type: research

Formation of Stable Ni(III) N-Confused Porphyrins Aided by 3-Ethoxy Group
We report the synthesis, characterization and reactivities of two stable Ni(III) N-confused porphyrin (NCP) complexes. Metalation of 3-OEt NCP 1 with NiCl 2 . 6H 2 O in CHCl 3 /EtOH gave 3-OEt Ni(II) NCP 3 initially, which was easily oxidized by air to form Ni(III) complex of NCP inner C-oxide 4 . Bis-ethoxy-modified Ni(III) complex 5 was synthesized by oxidation of 3 with PIFA in ethanol and CHCl 3 . Structures of 4 and 5 were determined by single-crystal X-ray diffraction analysis. An unusual long Ni(III)-C bond (2.170 (9) Å) was observed in 4 . The g-factor (g> 2.1) observed in the EPR spectra of 4 and 5 furthe...
Source: Chemistry - October 21, 2021 Category: Chemistry Authors: Huowang He Zongren Ye Daiki Shimizu Idrees Sumra Yihuan Zhang Zhengyu Liang Yingyu Zeng Ling Xu Atsuhiro Osuka Zhuofeng Ke Hua-Wei Jiang Source Type: research

Activation of Molecular O2 on CoFe2O4  (001) Surfaces: An Embedded Cluster Study
Chemistry. 2021 Oct 20. doi: 10.1002/chem.202102784. Online ahead of print.ABSTRACTDioxygen activation pathways on the (001) surfaces of cobalt ferrite, CoFe 2 O 4 , were investigated computationally using density functional theory and the hybrid Perdew-Burke-Ernzerhof exchange-correlation functional (PBE0) within the periodic electrostatic embedded cluster model. We considered two terminations: the A-layer exposing Fe 2+ and Co 2+ metal sites in tetrahedral and octahedral positions, respectively, and the B-layer exposing octahedrally coordinated Co 3+ . On the A-layer, molecular oxygen is chemisorbed as a superoxide on th...
Source: Chemistry - October 20, 2021 Category: Chemistry Authors: Arjeta Rushiti Christof H ättig Source Type: research

In Situ Electronegativity and the Bridging  of Chemical Bonding Concepts
We present a three-dimensional analysis of the electron energy density and use it to redefine what constitutes an atom in a molecule. Definitions of atomic partial charge and electronegativity follow in a way that connects these concepts to the total energy of a molecule. Formation of polar bonds are predicted to cause inversions of electronegativity and a new perspective of bonding in diborane and guanine-cytosine base-pairing is presented. Electronegativity of atoms inside molecules is shown to be predictive of pKa.PMID:34668618 | DOI:10.1002/chem.202103477 (Source: Chemistry)
Source: Chemistry - October 20, 2021 Category: Chemistry Authors: Stefano Racioppi Martin Rahm Source Type: research

Coordinatively Unsaturated Amidotitanocene Cations with Inverted σ and π Bond Strengths: Controlled Release of Aminyl Radicals and Hydrogenation/Dehydrogenation Catalysis
Chemistry. 2021 Oct 20. doi: 10.1002/chem.202103487. Online ahead of print.ABSTRACTCationic amidotitanocene complexes [Cp2Ti(NPhAr)][B(C6F5)4] (Cp = η5-C5H5; Ar = phenyl (1a), p-tolyl (1b), p-anisyl (1c)) were isolated. The bonding situation was studied by Density Functional Theory using EDA-NOCV (Energy Decomposition Analysis with Natural Orbitals for Chemical Valence). The polar Ti-N bond in 1a-c features an unusual inversion of σ and π bond strengths responsible for the balance between stability and reactivity in these coordinatively unsaturated species. In solution, 1a-c undergo photolytic Ti-N cleavage to...
Source: Chemistry - October 20, 2021 Category: Chemistry Authors: Adrien Thomas Normand Quentin Bonnin Tereza Edlov á E Daiann Sosa Carrizo Paul Fleurat-Lessard H élène Cattey Philippe Richard Pierre Le Gendre St éphane Brandès Source Type: research

A New Nonlinear Optical Material with  N(CN)2- Anion
Chemistry. 2021 Oct 20. doi: 10.1002/chem.202103355. Online ahead of print.ABSTRACTDiscovering new functional genes and developing high-performance materials are the goals being pursued by scientists. In this work, we successfully obtained a second-order nonlinear optical (NLO) material via the aqueous solution method, Y[N(CN) 2 ] 4 [NH(C 2 H 5 ) 3 ]∙3H 2 O, which is the first NLO material with anionic group N(CN) 2 - . Remarkably, this material not only is strongly NLO-active at 1064 nm with a response of about 2.8 × KH 2 PO 4 , but also possesses a short UV absorption edge of 250 nm. In-depth first-principles cal...
Source: Chemistry - October 20, 2021 Category: Chemistry Authors: Xin Chen Han Wang Youchao Liu Yang Zhou Weiqi Huang Minjuan Li Yanqiang Li Yangxin Chen Sangen Zhao Junhua Luo Source Type: research

Activation of Molecular O2 on CoFe2O4  (001) Surfaces: An Embedded Cluster Study
Chemistry. 2021 Oct 20. doi: 10.1002/chem.202102784. Online ahead of print.ABSTRACTDioxygen activation pathways on the (001) surfaces of cobalt ferrite, CoFe 2 O 4 , were investigated computationally using density functional theory and the hybrid Perdew-Burke-Ernzerhof exchange-correlation functional (PBE0) within the periodic electrostatic embedded cluster model. We considered two terminations: the A-layer exposing Fe 2+ and Co 2+ metal sites in tetrahedral and octahedral positions, respectively, and the B-layer exposing octahedrally coordinated Co 3+ . On the A-layer, molecular oxygen is chemisorbed as a superoxide on th...
Source: Chemistry - October 20, 2021 Category: Chemistry Authors: Arjeta Rushiti Christof H ättig Source Type: research

In Situ Electronegativity and the Bridging  of Chemical Bonding Concepts
We present a three-dimensional analysis of the electron energy density and use it to redefine what constitutes an atom in a molecule. Definitions of atomic partial charge and electronegativity follow in a way that connects these concepts to the total energy of a molecule. Formation of polar bonds are predicted to cause inversions of electronegativity and a new perspective of bonding in diborane and guanine-cytosine base-pairing is presented. Electronegativity of atoms inside molecules is shown to be predictive of pKa.PMID:34668618 | DOI:10.1002/chem.202103477 (Source: Chemistry)
Source: Chemistry - October 20, 2021 Category: Chemistry Authors: Stefano Racioppi Martin Rahm Source Type: research

Coordinatively Unsaturated Amidotitanocene Cations with Inverted σ and π Bond Strengths: Controlled Release of Aminyl Radicals and Hydrogenation/Dehydrogenation Catalysis
Chemistry. 2021 Oct 20. doi: 10.1002/chem.202103487. Online ahead of print.ABSTRACTCationic amidotitanocene complexes [Cp2Ti(NPhAr)][B(C6F5)4] (Cp = η5-C5H5; Ar = phenyl (1a), p-tolyl (1b), p-anisyl (1c)) were isolated. The bonding situation was studied by Density Functional Theory using EDA-NOCV (Energy Decomposition Analysis with Natural Orbitals for Chemical Valence). The polar Ti-N bond in 1a-c features an unusual inversion of σ and π bond strengths responsible for the balance between stability and reactivity in these coordinatively unsaturated species. In solution, 1a-c undergo photolytic Ti-N cleavage to...
Source: Chemistry - October 20, 2021 Category: Chemistry Authors: Adrien Thomas Normand Quentin Bonnin Tereza Edlov á E Daiann Sosa Carrizo Paul Fleurat-Lessard H élène Cattey Philippe Richard Pierre Le Gendre St éphane Brandès Source Type: research

A New Nonlinear Optical Material with  N(CN)2- Anion
Chemistry. 2021 Oct 20. doi: 10.1002/chem.202103355. Online ahead of print.ABSTRACTDiscovering new functional genes and developing high-performance materials are the goals being pursued by scientists. In this work, we successfully obtained a second-order nonlinear optical (NLO) material via the aqueous solution method, Y[N(CN) 2 ] 4 [NH(C 2 H 5 ) 3 ]∙3H 2 O, which is the first NLO material with anionic group N(CN) 2 - . Remarkably, this material not only is strongly NLO-active at 1064 nm with a response of about 2.8 × KH 2 PO 4 , but also possesses a short UV absorption edge of 250 nm. In-depth first-principles cal...
Source: Chemistry - October 20, 2021 Category: Chemistry Authors: Xin Chen Han Wang Youchao Liu Yang Zhou Weiqi Huang Minjuan Li Yanqiang Li Yangxin Chen Sangen Zhao Junhua Luo Source Type: research

Interplay of Polarity and Confinement in Asymmetric Catalysis with Chiral Rh Diene Complexes in Microemulsions
Chemistry. 2021 Oct 19. doi: 10.1002/chem.202102752. Online ahead of print.ABSTRACTMicroemulsions provide a unique opportunity to tailor the polarity and liquid confinement in asymmetric catalysis via nanoscale polar and nonpolar domains separated by a surfactant film. For chiral diene Rh complexes, the influence of counterion and surfactant film on the catalytic activity and enantioselectivity remained elusive. To explore this issue chiral norbornadiene Rh(X) complexes (X = OTf, OTs, OAc, PO 2 F 2 ) were synthesized and characterized by X-ray crystallography and theoretical calculations. These complexes were used in Rh-ca...
Source: Chemistry - October 19, 2021 Category: Chemistry Authors: Sabine Laschat Manuel Kirchhof Karina Abitaev Abdulwahab Abouhaileh Katrin Gugeler Wolfgang Frey Anna Zens Johannes K ästner Thomas Sottmann Source Type: research

N-amino- ​1,​8-​naphthalimide is a regenerated protecting group for selective synthesis of mono N-substituted hydrazines and hydrazides
Chemistry. 2021 Oct 19. doi: 10.1002/chem.202102593. Online ahead of print.ABSTRACTWe have invented a new route to synthesis of various mono N-substituted hydrazines and hydrazides by involving in a new C-N bond formation using N-amino-​1,​8-​naphthalimide as a regenerated precursor. Aniline and phenylhydrazines are reproduced upon reacting these individually with 1,8-naphthalic anhydride followed by hydrazinolysis. The practicality and simplicity of this C-N bond formation protocol was exemplified to various hydrazines and hydrazides. N-amino-​1,​8-​naphthalimide is suitable synthon for transformation for sele...
Source: Chemistry - October 19, 2021 Category: Chemistry Authors: Venkataramana Parikibanda Manoj Kumar Mesram Yadaiah Chityala Yadagiri Swamy Parikibanda Source Type: research

Azimuthal Dipolar Rotor Arrays on Surfaces
Chemistry. 2021 Oct 19. doi: 10.1002/chem.202103237. Online ahead of print.ABSTRACTA set of dipolar molecular rotor compounds was designed, synthesized and adsorbed as self-assembled 2D arrays on Ag(111) surfaces. The title molecules are constructed from three building blocks: (a) 4,8,12-trioxatriangulene (TOTA) platforms that are known to physisorb on metal surfaces such as Au(111) and Ag(111), (b) phenyl groups attached to the central carbon atom that function as pivot joints to reduce the barrier to rotation, (c) pyridine and pyridazine units as small dipolar units on top. Theoretical calculations and STM investigations...
Source: Chemistry - October 19, 2021 Category: Chemistry Authors: Rainer Herges Sebastian Hamer Jan-Simon von Glasenapp Fynn R öhricht Richard Berndt Chao Li Source Type: research

Exploiting the structural metamorphosis of polymers to 'wrap'  micron-sized spherical objects
We describe the successful 'wrapping' of lectin-decorated microspheres, which serve as appealing model micron-sized objects, within cross-linked polymer film. This approach utilizes polymer chains able to undergo a structural metamorphosis, from being intramolecularly cross-linked to intermoleculary cross-linked, a process that is triggered by polymer concentration upon the particle surface. Experiments demonstrate that both complementary molecular recognition and the dynamic covalent nature of the crosslinker are required for successful 'wrapping' to occur. This work is significant as it suggests that nano- and micron-siz...
Source: Chemistry - October 19, 2021 Category: Chemistry Authors: Patrick L Higgs Jordan L Appleton Bruce W Turnbull David Andrew Fulton Source Type: research

Total syntheses of conjugation-ready repeating units of Acinetobacter baumannii AB5075 for glycoconjugate vaccine development
Chemistry. 2021 Oct 19. doi: 10.1002/chem.202103234. Online ahead of print.ABSTRACTAcinetobacter baumannii is an opportunistic pathogen that causes serious nosocomial infections. One of the multidrug-resistant strains, AB5075, can result in bacteremia, pneumonia and wound infections associated with high morbidity and mortality. The structurally unique glycans on the surface of these bacteria are attractive targets for the development of glycoconjugate vaccines. Here, we report the first total synthesis of the densely functionalized trisaccharide repeating unit of A. baumannii AB5075 as well as two analogues. The constructi...
Source: Chemistry - October 19, 2021 Category: Chemistry Authors: Shuo Zhang Peter H Seeberger Source Type: research

Incorporation of β-alanine in Cu(II) ATCUN peptide complexes increases ROS levels, DNA cleavage and antiproliferative activity
Chemistry. 2021 Oct 17. doi: 10.1002/chem.202102601. Online ahead of print.ABSTRACTRedox active Cu(II) complexes are able to form reactive oxygen species (ROS) in the presence of oxygen and reducing agents. Recently, Faller et al. reported that ROS generation by Cu(II) ATCUN complexes is not as high as assumed for decades. High complex stability results in silencing of the Cu(II)/Cu(I) redox cycle and therefore to low ROS generation. In this work, we demonstrate that an exchange of the a -amino acid Gly with the β-amino acid β-Ala at position 2 (Gly2 → β-Ala2) of the ATCUN motif reinstates ROS productio...
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: Julian Heinrich Karolina Bossad-Ahmad Mie Riisom Haleh H Haeri Tasha R Steel Vinja Hergl Alexander Langhans Corinna Schattschneider Jannis Barrera Stephen M F Jamieson Matthias Stein Dariush Hinderberger Christian G Hartinger Wojciech Bal Nora Kulak Source Type: research

Expedient Access to Cyanated N-Heterocycles via Direct Flow-Electrochemical C(sp2)-H Activation
Chemistry. 2021 Oct 18. doi: 10.1002/chem.202103384. Online ahead of print.ABSTRACTNitriles are recurring motifs in bioactive molecules and versatile functional groups in synthetic chemistry. Despite recent progress, direct introduction of a nitrile moiety in heteroarenes remains challenging. Recent developments in electrochemical reactions pave the way to more practical cyanation protocols. However, currently available methods typically require hazardous cyanide sources, expensive mediators, and often suffer from narrow substrate scope and laborious reaction set-up. To address the limitations of current synthetic methods,...
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: Mary-Ambre Carvalho Samu ël Demin Carolina Martinez-Lamenca Fedor Romanov-Michailidis Kevin Lam Frederik Rombouts Morgan Lecomte Source Type: research

Putting anion- π interactions at work for catalysis
This article shortly illustrates the emergence and development of this concept, aiming to provide an emphasis on the general concept and key progress in this exciting area. To highlight the essential contribution of anion-π interactions, the contents are organized according to their role engaged in catalytic process, e.g. from both ground-state and transition-state stabilization to solely transition-state stabilization, mainly by a single π-face, and to cooperative π-face activation. A concluding remark and outlook on future development of this field is also given.PMID:34658085 | DOI:10.1002/chem.202103303 (Source: Chemistry)
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: Na Luo Yu-Fei Ao De-Xian Wang Qi-Qiang Wang Source Type: research

A novel route for the easy production of thermochromic VO2 nanoparticles
Chemistry. 2021 Oct 18. doi: 10.1002/chem.202102566. Online ahead of print.ABSTRACTIn this work, a simple, fast and dry method for the fabrication of a thermochromic product with a high load of VO 2 (M1) consisting of the controlled heat treatment of pure vanadium nanoparticles in air is presented. After a complete design of experiments, it is concluded that the most direct way to attain the maximum transformation of V into VO 2 (M1) consists of one cycle with a fast heating ramp of 42 o Cs -1 , followed by keeping 700 o C for 530-600 seconds, and a subsequent cooling at 0.05 o Cs -1 . Careful examination of these results ...
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: A J Santos M Escanciano A Su árez-Llorens M P Yeste Francisco M Morales Source Type: research

In situ observation of ferroelastic domain and phase transition in a three-dimensional molecular crystal
Chemistry. 2021 Oct 18. doi: 10.1002/chem.202103229. Online ahead of print.ABSTRACTMassive efforts have been devoted to designing molecular ferroic materials by molecular modification. For molecular ferroelastic, previous work is focused on the temperature-dependent ferroelastic domains, however, few are related to controlling the ferroelastic domain by the stress. Inspired by the "quasi-spherical theory" and fluorination effect, we designed a more flexible (MedabcoF) 2+ (MedabcoF= 1-fluoro-4-methyl-1,4-diazoniabicyclo[2.2.2]octane) cation by introducing a methyl group and a fluorine atom at the two symmetrical e...
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: Sai-Nan Cheng Kun Ding Tie Zhang Zhi-Xu Zhang Chang-Yuan Su Jia-Zhen Ge Yi Zhang Da-Wei Fu Source Type: research

Incorporation of β-alanine in Cu(II) ATCUN peptide complexes increases ROS levels, DNA cleavage and antiproliferative activity
Chemistry. 2021 Oct 17. doi: 10.1002/chem.202102601. Online ahead of print.ABSTRACTRedox active Cu(II) complexes are able to form reactive oxygen species (ROS) in the presence of oxygen and reducing agents. Recently, Faller et al. reported that ROS generation by Cu(II) ATCUN complexes is not as high as assumed for decades. High complex stability results in silencing of the Cu(II)/Cu(I) redox cycle and therefore to low ROS generation. In this work, we demonstrate that an exchange of the a -amino acid Gly with the β-amino acid β-Ala at position 2 (Gly2 → β-Ala2) of the ATCUN motif reinstates ROS productio...
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: Julian Heinrich Karolina Bossad-Ahmad Mie Riisom Haleh H Haeri Tasha R Steel Vinja Hergl Alexander Langhans Corinna Schattschneider Jannis Barrera Stephen M F Jamieson Matthias Stein Dariush Hinderberger Christian G Hartinger Wojciech Bal Nora Kulak Source Type: research

Expedient Access to Cyanated N-Heterocycles via Direct Flow-Electrochemical C(sp2)-H Activation
Chemistry. 2021 Oct 18. doi: 10.1002/chem.202103384. Online ahead of print.ABSTRACTNitriles are recurring motifs in bioactive molecules and versatile functional groups in synthetic chemistry. Despite recent progress, direct introduction of a nitrile moiety in heteroarenes remains challenging. Recent developments in electrochemical reactions pave the way to more practical cyanation protocols. However, currently available methods typically require hazardous cyanide sources, expensive mediators, and often suffer from narrow substrate scope and laborious reaction set-up. To address the limitations of current synthetic methods,...
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: Mary-Ambre Carvalho Samu ël Demin Carolina Martinez-Lamenca Fedor Romanov-Michailidis Kevin Lam Frederik Rombouts Morgan Lecomte Source Type: research

Putting anion- π interactions at work for catalysis
This article shortly illustrates the emergence and development of this concept, aiming to provide an emphasis on the general concept and key progress in this exciting area. To highlight the essential contribution of anion-π interactions, the contents are organized according to their role engaged in catalytic process, e.g. from both ground-state and transition-state stabilization to solely transition-state stabilization, mainly by a single π-face, and to cooperative π-face activation. A concluding remark and outlook on future development of this field is also given.PMID:34658085 | DOI:10.1002/chem.202103303 (Source: Chemistry)
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: Na Luo Yu-Fei Ao De-Xian Wang Qi-Qiang Wang Source Type: research

A novel route for the easy production of thermochromic VO2 nanoparticles
Chemistry. 2021 Oct 18. doi: 10.1002/chem.202102566. Online ahead of print.ABSTRACTIn this work, a simple, fast and dry method for the fabrication of a thermochromic product with a high load of VO 2 (M1) consisting of the controlled heat treatment of pure vanadium nanoparticles in air is presented. After a complete design of experiments, it is concluded that the most direct way to attain the maximum transformation of V into VO 2 (M1) consists of one cycle with a fast heating ramp of 42 o Cs -1 , followed by keeping 700 o C for 530-600 seconds, and a subsequent cooling at 0.05 o Cs -1 . Careful examination of these results ...
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: A J Santos M Escanciano A Su árez-Llorens M P Yeste Francisco M Morales Source Type: research

In situ observation of ferroelastic domain and phase transition in a three-dimensional molecular crystal
Chemistry. 2021 Oct 18. doi: 10.1002/chem.202103229. Online ahead of print.ABSTRACTMassive efforts have been devoted to designing molecular ferroic materials by molecular modification. For molecular ferroelastic, previous work is focused on the temperature-dependent ferroelastic domains, however, few are related to controlling the ferroelastic domain by the stress. Inspired by the "quasi-spherical theory" and fluorination effect, we designed a more flexible (MedabcoF) 2+ (MedabcoF= 1-fluoro-4-methyl-1,4-diazoniabicyclo[2.2.2]octane) cation by introducing a methyl group and a fluorine atom at the two symmetrical e...
Source: Chemistry - October 18, 2021 Category: Chemistry Authors: Sai-Nan Cheng Kun Ding Tie Zhang Zhi-Xu Zhang Chang-Yuan Su Jia-Zhen Ge Yi Zhang Da-Wei Fu Source Type: research

Metal-to-Metal Distance Modulated Au(I)/Ru(II) Cyclophanyl Complexes: Cooperative Effects in Photoredox Catalysis
Chemistry. 2021 Oct 16. doi: 10.1002/chem.202102341. Online ahead of print.ABSTRACTThe modular synthesis of Au(I)/Ru(II) decorated mono- and heterobimetallic complexes with π-conjugated [2.2]paracyclophane is described. [2.2]Paracyclophane serves as a rigid spacer which holds the metal centers in precise spatial orientations and allows metal-to-metal distance modulation. A broad set of architectural arrangements of pseudo - gem , - ortho , - meta , and - para substitution patterns were employed. Metal-to-metal distance modulation of AuRu heterobimetallic complexes and the innate transannular π-communication of the cy...
Source: Chemistry - October 16, 2021 Category: Chemistry Authors: Christoph Zippel Roumany Israil Lars Sch üssler Zahid Hasan Erik Schneider Patrick Weis Martin Nieger Claudia Bizzarri Manfred M Kappes Christoph Riehn Rolf Diller Stefan Br äse Source Type: research

Metal-to-Metal Distance Modulated Au(I)/Ru(II) Cyclophanyl Complexes: Cooperative Effects in Photoredox Catalysis
Chemistry. 2021 Oct 16. doi: 10.1002/chem.202102341. Online ahead of print.ABSTRACTThe modular synthesis of Au(I)/Ru(II) decorated mono- and heterobimetallic complexes with π-conjugated [2.2]paracyclophane is described. [2.2]Paracyclophane serves as a rigid spacer which holds the metal centers in precise spatial orientations and allows metal-to-metal distance modulation. A broad set of architectural arrangements of pseudo - gem , - ortho , - meta , and - para substitution patterns were employed. Metal-to-metal distance modulation of AuRu heterobimetallic complexes and the innate transannular π-communication of the cy...
Source: Chemistry - October 16, 2021 Category: Chemistry Authors: Christoph Zippel Roumany Israil Lars Sch üssler Zahid Hasan Erik Schneider Patrick Weis Martin Nieger Claudia Bizzarri Manfred M Kappes Christoph Riehn Rolf Diller Stefan Br äse Source Type: research

Metal-to-Metal Distance Modulated Au(I)/Ru(II) Cyclophanyl Complexes: Cooperative Effects in Photoredox Catalysis
Chemistry. 2021 Oct 16. doi: 10.1002/chem.202102341. Online ahead of print.ABSTRACTThe modular synthesis of Au(I)/Ru(II) decorated mono- and heterobimetallic complexes with π-conjugated [2.2]paracyclophane is described. [2.2]Paracyclophane serves as a rigid spacer which holds the metal centers in precise spatial orientations and allows metal-to-metal distance modulation. A broad set of architectural arrangements of pseudo - gem , - ortho , - meta , and - para substitution patterns were employed. Metal-to-metal distance modulation of AuRu heterobimetallic complexes and the innate transannular π-communication of the cy...
Source: Chemistry - October 16, 2021 Category: Chemistry Authors: Christoph Zippel Roumany Israil Lars Sch üssler Zahid Hasan Erik Schneider Patrick Weis Martin Nieger Claudia Bizzarri Manfred M Kappes Christoph Riehn Rolf Diller Stefan Br äse Source Type: research

A Lead Mixed Halide with Three Different Coordinated Anions and Strong Second-Harmonic Generation Response
This study points out an effective strategy to develop new NLO crystals with strong SHG response.PMID:34651354 | DOI:10.1002/chem.202103687 (Source: Chemistry)
Source: Chemistry - October 15, 2021 Category: Chemistry Authors: Ruibiao Fu Qirui Shui Zuju Ma Ziqi Zhou Hongxin Tamg Xintao Wu Source Type: research

Host-Guest Systems on the Surface of Functionalized Superparamagnetic Iron Oxide Nanoparticles (SPIONs) Utilizing Hamilton Receptors and Cyanurate Derivative Molecules
Chemistry. 2021 Oct 15. doi: 10.1002/chem.202102581. Online ahead of print.ABSTRACTThe study of hydrogen bonding interactions at the level of functionalized nanoparticles remains highly challenging and poorly explored area. In this work, superparamagnetic iron oxide nanoparticles (SPIONs) were orthogonally functionalized using receptors bearing multiple hydrogen bonding motifs. Pristine SPIONs were modified by wet chemical processes with Hamilton receptors (hosts), or cyanurate-guest molecules linked to phosphonic acid moieties for monolayer functionalization. The modified surfaces were fully characterized and the number o...
Source: Chemistry - October 15, 2021 Category: Chemistry Authors: Andreas Hirsch Muhammad Ali Evgeny Kataev Johannes M üller Hyoungwon Park Marcus Halik Source Type: research

Easy Production of "Difficult Peptides" using Cell-Free Protein Synthesis and a New Methionine Analogue as a Latent Peptide Cleavage Site
Chemistry. 2021 Oct 14. doi: 10.1002/chem.202103161. Online ahead of print.ABSTRACTAliphatic γ-chloro-α-amino acids incorporated in place of their canonical analogues through cell-free protein synthesis act as heat-labile linkers, offering a useful strategy for the straightforward production of target peptides as fusion proteins, from which the targets are readily released. Until now, the natural abundance of aliphatic amino acids in peptides has limited the scope of the method, as it leads to undesired cleavage sites in synthesized products, but here we report the development of a new cleavable chloro amino ac...
Source: Chemistry - October 15, 2021 Category: Chemistry Authors: Daniel Fankhauser Apostolos Alissandratos Mantas Liutkus Christopher J Easton Source Type: research

On-Surface formation of Cyano-Vinylene Linked Chains by Knoevenagel Condensation
Chemistry. 2021 Oct 15. doi: 10.1002/chem.202103094. Online ahead of print.ABSTRACTThe rapid development of on-surface synthesis provides a unique approach toward the formation of carbon-based nanostructures with designed properties. Herein, we present the on-surface formation of CN-substituted phenylene vinylene chains on the Au(111) surface, thermally induced by annealing the substrate stepwise at temperatures between 220°C and 240°C. The reaction is investigated by scanning tunneling microscopy and density functional theory. Supported by the calculated reaction pathway, we assign the observed chain formation to ...
Source: Chemistry - October 15, 2021 Category: Chemistry Authors: Francesca Moresco Kwan Ho Au-Yeung Tim K ühne Daniel Becker Marcus Richter Dmitry A Ryndyk Gianaurelio Cuniberti Thomas Heine Xinliang Feng Source Type: research

4-Phosphoryl pyrazolones for highly selective lithium separation from alkali metal ions
In this study, it is demonstrated that the 4-phosphoryl pyrazolones, H L 2 -H L 4 , in the presence of the typical industrial organophosphorus co-ligands tributylphosphine oxide (TBPO), tributylphosphate (TBP) and trioctylphosphine oxide (TOPO), are able to selectively recognise and extract lithium ions from aqueous solution. Structural investigations in solution as well as in the solid state reveal the existence of a series of multinuclear Li + complexes that include dimers (TBPO, TBP) as well as rarely observed trimers (TOPO) and represent the first clear evidence for the synergistic role of the co-ligands in the extract...
Source: Chemistry - October 15, 2021 Category: Chemistry Authors: Jan J Weigand Jianfeng Zhang Marco Wenzel Johannes Steup Gerrit Schaper Felix Hennersdorf Hao Du Shili Zheng Leonard F Lindoy Source Type: research

A copper(I)-catalyzed sulfonylative Hiyama cross-coupling
Chemistry. 2021 Oct 15. doi: 10.1002/chem.202103371. Online ahead of print.ABSTRACTAn air-tolerant Cu-catalyzed sulfonylative Hiyama crosscoupling reaction enabling the formation of diaryl sulfones is described. Starting from aryl silanes, DABSO and aryliodides, the reaction tolerates a large variety of polar functional groups (amines, ketones, esters, aldehydes). Control experiments coupled with DFT calculations shed light on the mechanism, characterized by the formation of a Cu(I)-sulfinate intermediate via fast insertion of a SO 2 molecule.PMID:34652867 | DOI:10.1002/chem.202103371 (Source: Chemistry)
Source: Chemistry - October 15, 2021 Category: Chemistry Authors: Aur élien Adenot Lucile Anthore-Dalion Emmanuel Nicolas Jean-Claude Berthet Pierre Thu éry Thibault Cantat Source Type: research

Rhodium Indenyl NHC and Fluorenyl-Tethered-NHC Half-Sandwich Complexes: Synthesis, Structures and Applications in the Catalytic C-H Borylation of Arenes and Alkanes
Chemistry. 2021 Oct 15. doi: 10.1002/chem.202102961. Online ahead of print.ABSTRACTIndenyl rhodium NHC complexes [Rh(η5-Ind)(NHC)(L)] were synthesised for SIPr with L = C2H4 (1), CO (2a) and COE (3), for SIMes with L = CO (2b) and COE (4), and IMes with L = CO (2c) and COE (5). Reaction of SIPr with [Rh(Cp*)(C2H4)2] did not give the desired SIPr complex demonstrating the 'indenyl effect' in the synthesis of 1 . Oxidative addition of HSi(OEt)3 to 3 proceeded under mild conditions to give the Rh silyl hydride complex [Rh(Ind){Si(OEt)3}(H)(SIPr)] (6). Tethered-fluorenyl-NHC rhodium complexes [Rh{(η5-C13H8)C2H4N(C)C2Hx...
Source: Chemistry - October 15, 2021 Category: Chemistry Authors: Kieren J Evans Paul A Morton Christian Luz Callum Miller Olivia Raine Jason M Lynam Stephen Michael Mansell Source Type: research

Control of protonated Schiff base excited state decay within visual protein mimics: a unified model for retinal chromophores
Chemistry. 2021 Oct 15. doi: 10.1002/chem.202102383. Online ahead of print.ABSTRACTArtificial biomimetic chromophore-protein complexes inspired by natural visual pigments can feature color tunability across the full visible spectrum. However, control of excited state dynamics of the retinal chromophore, which is of paramount importance for technological applications, is lacking due to its complex and subtle photophysics/photochemistry. Here, we combine ultrafast transient absorption spectroscopy and quantum mechanics/molecular mechanics simulations for the study of highly-tunable rhodopsin mimics, as compared to retinal ch...
Source: Chemistry - October 15, 2021 Category: Chemistry Authors: Marco Garavelli Baptiste Demoulin Margherita Maiuri Tetyana Berbasova James Geiger Babak Borhan Giulio Cerullo Ivan Rivalta Source Type: research

Early Physical Organic Chemistry: Nikolai Aleksandrovich Menshutkin (1842-1907) and Reaction Velocities
Chemistry. 2021 Oct 13. doi: 10.1002/chem.202101823. Online ahead of print.ABSTRACTThe name of Menshutkin is most frequently associated with his eponymous reaction (the quaternization of tertiary amines with alkyl halides). However, he made encyclopedic contributions to the field of reaction kinetics, where he carried out extensive studies of the effects of reactant structure on the rates of esterification of monohydric, dihydric and trihydric alcohols with monocarboxylic acids, and monobasic and dibasic carboxylic acids and anhydrides with monohydric alcohols. In these studies, he deduced an order of reactivity of alcohol...
Source: Chemistry - October 14, 2021 Category: Chemistry Authors: David E Lewis Source Type: research

Synergy of Bi2O3 and RuO2 nanocatalysts for low-overpotential and wide pH-window electrochemical ammonia synthesis
Chemistry. 2021 Oct 13. doi: 10.1002/chem.202103143. Online ahead of print.ABSTRACTElectrocatalytic nitrogen reduction reaction (NRR) under ambient conditions is still seriously impeded by the inferior NH3 yield and low Faradic efficiency, especially at low overpotentials. Herein, we report the synthesis of nano-sized RuO2 and Bi2O3 particles grown on functionalized exfoliated graphene (FEG) through in-situ electrodeposition, denoted as RuO2-Bi2O3/FEG. The prepared self-supporting RuO2-Bi2O3/FEG hybrid with a Bi mass loading of 0.70 wt% and Ru mass loading of 0.04 wt% shows excellent NRR performance at low overpotentials i...
Source: Chemistry - October 14, 2021 Category: Chemistry Authors: Qiaoling Wu Bing Yu Zizhao Deng Li Tianyan Hui Li Baohua Jia Peng Li Wenping Sun Ximing Song Ying Sun Tianyi Ma Source Type: research

Difluorocarbene-Induced Ring-Opening Difluoromethylation-Halogenation of Cyclic (Thio)Ethers with TMSCF2X (X = Br, Cl)
Chemistry. 2021 Oct 14. doi: 10.1002/chem.202103428. Online ahead of print.ABSTRACTThe ring-opening difluoromethylation-halogenation of cyclic(thio)ethers is reported via a simple strategy relying on carbon-chalcogen bond activation with difluorocarbene. The reaction proceeds through in-situ protonation of the previously little-known difluoromethylene oxonium or sulfonium ylide intermediate followed by ring-opening with halide ion to afford halogenated acyclic difluoromethyl (thio)ethers that can then be employed for further elaboration. TMSCF2X (X = Br, Cl) are unique reagents to achieve this synthetic purpose, which serv...
Source: Chemistry - October 14, 2021 Category: Chemistry Authors: Rongyi Zhang Qigang Li Qiqiang Xie Chuanfa Ni Jinbo Hu Source Type: research

In situ generation of CoCeSx bimetallic sulfide nanoparticles on graphene composite modified by bi-pyrene terminated molecular for supercapacitors
Chemistry. 2021 Oct 14. doi: 10.1002/chem.202103145. Online ahead of print.ABSTRACTGraphene's excellent electrical conductivity benefits from its highly-conjugated structure. Therefore, the manipulation of graphene's electronic and mechanical properties can be realized by controlled destruction of its in-sheet conjugation system. Herein, we report the preparation of CoCeS x -SA@BPMW@RGO via π-π stacking interactions at molecular level. In detail, sodium alginate was compounded with Co 2+ and Ce 3+ , the composite was loaded onto graphene. The graphene sheets are propped by bi-pyrene terminated molecular wire (BPMW) t...
Source: Chemistry - October 14, 2021 Category: Chemistry Authors: Jingquan Liu Wenjun Huang Aitang Zhang Hucheng Fu Maozhuang Zhang Wenting Cheng Wenrong Yang Colin Barrow Source Type: research

Emerging Design Principle of Near-Infrared Upconversion Sensitizer Based on Mitochondria-Targeted Organic Dye for Enhanced Photodynamic Therapy
Chemistry. 2021 Oct 14. doi: 10.1002/chem.202102866. Online ahead of print.ABSTRACTUpconversion luminescent (UCL) triggered photodynamic therapy (PDT) affords superior outcome for cancer treatment. However, conventional UCL materials which all work as multiphoton absorption (MPA) process, inevitably need extremely high power density far over the maximum permissible exposure (MPE) to laser. Here, an one-photon absorption molecular upconversion sensitizer Cy5.5-Br based on frequency upconversion luminescent (FUCL) is designed for PDT. The unusual super heavy atom effect (SHAE) in Cy5.5-Br strongly enhance its spin-orbit coup...
Source: Chemistry - October 14, 2021 Category: Chemistry Authors: Ruisong Tian Chao Wang Weijie Chi Jiangli Fan Jianjun Du Saran Long Lianying Guo Xiaogang Liu Xiaojun Peng Source Type: research

The Electrochemical cis-Chlorination of Alkenes
Chemistry. 2021 Oct 14. doi: 10.1002/chem.202103316. Online ahead of print.ABSTRACTDouble Role - the cis-chlorination of alkenes is realised in an electrochemical setup with PhSeCl as catalyst. The supporting electrolyte (TBACl) acts as nucleophilic reagent for the SN2-type replacemant of the selenium versus chloride in the key step of the process while the PhSeCl-adduct is activated by electrochemically generated PhSeCl3.PMID:34648232 | DOI:10.1002/chem.202103316 (Source: Chemistry)
Source: Chemistry - October 14, 2021 Category: Chemistry Authors: Julia Strehl Cornelius Fastie Gerhard Hilt Source Type: research

Investigation of bis(perfluoro-tert-butoxy) halogenates(I/III)
We present a systematic study of halogenate(I/III) anions with polyatomic ligands. The bis(perfluoro- tert -butoxy) halogenates(I) [X(OC 4 F 9 ) 2 ] - , X = Cl, Br, I, of chlorine, bromine, and iodine are prepared as their tetraethylammonium salts and characterized with IR, Raman and NMR spectroscopic methods as well as single-crystal X-ray diffraction. Spectroscopical data are supported by quantum-chemical calculations. Additionally, the bonding situation of the species in question are analyzed and discussed. Furthermore, we studied the oxidation to the corresponding halogenate(III) derivatives. For [Br(OC 4 F 9 ) 2 ] - o...
Source: Chemistry - October 14, 2021 Category: Chemistry Authors: Sebastian Hasenstab-Riedel Patrick Pr öhm Willi R Berg Susanne M Rupf Patrick Vo ßnacker Source Type: research

Synergy of Iron Doping and Cyano Groups for Enhanced Photocatalytic Hydrogen Production over C3N4
Chemistry. 2021 Oct 14. doi: 10.1002/chem.202103092. Online ahead of print.ABSTRACTImproving the insufficient carrier separation dynamics is still of significant in carbon nitride (C 3 N 4 ) research . Extensive research has been devoted to improving the carrier separation efficiency through a single strategy, while ignoring the synergistic enhancement effect produced by coupling two or more conventional strategies. Herein, we reported the fabrication of cyano group-containing Fe-doped C 3 N 4 porous materials via direct co-calcination of iron acetylacetonate and melamine for synergistically improving the photocatalytic pe...
Source: Chemistry - October 14, 2021 Category: Chemistry Authors: Jie Xiao Jing-Wen Zhang Jiaxiang Zhang Lun Pan Chengxiang Shi Xiangwen Zhang Ji-Jun Zou Source Type: research