Conversion of Carbon Dioxide into a Series of CBO Compounds Mediated by LaBO Anions: Synergy of the Electron Transfer and Lewis Pair Mechanisms to Construct B-C Bonds.

Converting CO into value-added products containing B-C bonds is a great challenge, especially for multiple B-C bonds, which are versatile building blocks for organoborane chemistry. In the condensed phase, the B-C bond is typically formed through transition metal-catalyzed direct borylation of hydrocarbons via C-H bond activation or transition metal-catalyzed insertion of carbenes into B-H bonds. However, excessive amounts of powerful boryl reagents are required, and products containing B-C bonds are complex.

Consecutive Reduction of Five Carbon Dioxide Molecules by Gas-Phase Niobium Carbide Cluster Anions NbC: Unusual Mechanism for Enhanced Reactivity by the Carbon Ligands.

Studying the cleavage of the C═O bond during CO activation at room temperature is highly significant for comprehending the CO conversion processes. Herein, mass spectrometry experiments and density functional theory calculations indicate that the niobium carbide anions NbC can continuously convert five CO molecules to CO under thermal collision conditions, while the other clusters with less carbon ligands NbC reduce fewer CO molecules. Size-dependent reactivity of NbC cluster anions toward CO is observed.

Nitrogen adsorption on NbCH cations: the important role of benzyne (-CH).

N adsorption is a prerequisite for activation and transformation. Time-of-flight mass spectrometry experiments show that the NbCH cation, resulting from the gas-phase reaction of Nb with CH, is more favorable for N adsorption than Nb and Nb cations. Density functional theory calculations reveal the effect of the -CH ligand on N adsorption.

Activation and Transformation of Methane on Boron-Doped Cobalt Oxide Cluster Cations CoBO.

The cleavage of inert C-H bonds in methane at room temperature and the subsequent conversion into value-added products are quite challenging. Herein, the reactivity of boron-doped cobalt oxide cluster cations CoBO toward methane under thermal collision conditions was studied by mass spectrometry experiments and quantum-chemical calculations. In this reaction, one H atom and the CH unit of methane were transformed separately to generate the product metaboric acid (HBO) and one CoCH ion, respectively.

Manipulating Reactivity of Ir(CH) Cations toward Dinitrogen at Room Temperature: A Unique Dependence on the Organic Ligand Structures.

Nitrogen (N) activation at room temperature has long been a great challenge. Therefore, the rational design of reactive species to adsorb N, which is a prerequisite for cleavage of the strong N≡N triple bond in industrial and biological processes, is highly desirable and meaningful. Herein, the N adsorption process is controlled by regulating the types and numbers of organic ligands, and the organic ligands are produced through the reactions of Ir with methane and ethane.

Coupling of N and O in the Gas Phase to Synthesize Nitric Oxide at Room Temperature: A Zeldovich-Like Strategy.

Dinitrogen (N) activation and its chemical transformations are some of the most challenging topics in chemistry. Herein, we report that heteronuclear metal anions AuNbBO can mediate the direct coupling of N and O to generate NO molecules. N first forms the nondissociative adsorption product AuNbBON on AuNbBO.

Conversion of Dinitrogen and Oxygen to Nitric Oxide Mediated by Triatomic Yttrium Cations: Reversible N-N Bond Switching.

The direct coupling of dinitrogen (N) and oxygen (O) to produce value-added chemicals such as nitric acid (HNO) at room temperature is fascinating but quite challenging because of the inertness of N molecules. Herein, an interesting reaction pathway is proposed for a direct conversion of N and O mediated by all-metal Y cations. This reaction pattern begins with the N≡N triple bond cleavage by Y to generate a dinitride cation YN, and the electrons that lead to N activation in this process mainly originate from Y atoms.

Two Carbon Dioxide Molecules Consecutively Reduced by Metal-Free BO Anions.

Compared with transition metals, nonmetallic elements have always been considered to have low reactivity toward carbon dioxide. However, in recent years, main-group compounds such as boron-based species have gradually attracted increasing attention due to their prospective applications in different kinds of reactions. Herein, we report that metal-free anions BO can promote two CO reductions, producing the oxygen-rich product BO.

Direct Conversion of N and O to Nitric Oxide at Room Temperature Initiated by Double Aromaticity in the YBO Cation.

The conversion of dinitrogen to more useful and reactive molecules has been the focus of intense research by chemists. In contrast to reductive N fixation, direct oxidation of N by O to nitric oxide under mild conditions via a thermochemical process is extremely challenging. Herein, we report the first example of N and O activation and coupling under thermochemical conditions through the remarkable ability of YBO to react with one N and two O molecules.

Plasma-Assisted Coupling Reactions of Dinitrogen and Carbon Dioxide Mediated by Monometallic YB ⋅Anions: Carbon-Nitrogen Bond Formation.

Transition-metal catalyzed coupling to form C-N bonds is significant in chemical science. However, the inert nature of N and CO renders their coupling quite challenging. Herein, we report the activation of dinitrogen in the mild plasma atmosphere by the gas-phase monometallic YB anions and further coupling of CO to form C-N bonds by using mass spectrometry and theoretical calculation.

Experimental and Theoretical Study of N Adsorption on Hydrogenated YCH and Dehydrogenated YC Cluster Anions at Room Temperature.

The adsorption of atmospheric dinitrogen (N) on transition metal sites is an important topic in chemistry, which is regarded as the prerequisite for the activation of robust N≡N bonds in biological and industrial fields. Metal hydride bonds play an important part in the adsorption of N, while the role of hydrogen has not been comprehensively studied. Herein, we report the N adsorption on the well-defined YCH cluster anions under mild conditions by using mass spectrometry and density functional theory calculations.

Plasma-promoted reactions of the heterobimetallic anions CuNb with dinitrogen and subsequent reactions with carbon dioxide: formation of C-N bonds.

The activation and functionalization of dinitrogen with carbon dioxide into useful chemicals containing C-N bonds are significant research projects but highly challenging. Herein, we report that N molecules are dissociated by heterobimetallic CuNb anions assisted by surface plasma radiation, leading to the formation of CuNbN anions; the CuNbN anions can further react with CO to generate products NCO with one C-N bond and NbONCN with two C-N bonds under thermal collision conditions. For the activation of dinitrogen, the plasma atmosphere is conducive to the dissociation of the NN bond, which renders the coupling reactions of N and CO molecules easier to proceed.

Dinitrogen Activation by Dihydrogen and Quaternary Cluster Anions AuNbBO: Nb- and B-Mediated N Activation and Au-Assisted Nitrogen Transfer.

Nitrogen fixation and hydrogenation are important issues in chemistry and industry. Herein, we used mass spectrometry and quantum chemical calculations to identify the quaternary AuNbBO anions that can efficiently activate N and H to form imido (or amido) units in the products AuNbBONH under thermal collision conditions. In these reactions, Nb and B atoms work in synergy to dissociate N and the Au atom acts as a reducing agent, which facilitates the removal of one activated N atom for the following hydrogenation process; generation of three-centered, two-electron bonds facilitates N activation and N transformation.

Room-Temperature Dinitrogen and Carbon Dioxide Activation to Form Nitrogen-Carbon Bonds by Quaternary Cluster Anions: Gold-Assisted Enhancement of Reactivity.

Coupling conversion of CO and N molecules under mild conditions to form useful N-C bond-containing products has attracted significant attention. However, the activation and direct coupling of such very inert molecules are quite challenging. Herein, we determined that this coupling reaction can be realized by AuNbBO quaternary anions at room temperature.

Conversion of carbon dioxide to a novel molecule NCNBO mediated by NbBN anions at room temperature.

The activation of carbon dioxide (CO) mediated by NbBN cluster anions under the conditions of thermal collision has been investigated by time-of-flight mass spectrometry combined with density functional theory calculations. Two CO double bonds in the CO molecule are completely broken and two C-N bonds are further generated to form the novel molecule NCNBO. To the best of our knowledge, this new molecule is synthesized and reported for the first time.

Nitrogen Activation and Transformation on Monometallic Niobium Boron Oxide Cluster Anions at Room Temperature: A Dual-Site Mechanism.

Dinitrogen activation and transformation at room temperature is a goal that has been long sought after. Despite that, it remains underdeveloped due to being a challenging research area and the need for a better mechanistic understanding. Herein, we report that well-defined NbBO gas-phase clusters can activate one N molecule and generate the products BNO and BNO, as applying mass spectrometry and theoretical calculations.

Consecutive methane activation mediated by single metal boride cluster anions NbB.

Cleavage of all C-H bonds in two methane molecules by gas-phase cluster ions at room temperature is a challenging task. Herein, mass spectrometry and quantum chemical calculations have been used to identify one single metal boride cluster anions NbB4- that can activate eight C-H bonds in two methane molecules and release one H2 molecule each time under thermal collision conditions. In these consecutive reactions, the loaded Nb atoms and the support B4 units play different roles but act synergistically to activate CH4, which is responsible for the interesting reactivity of NbB4-.

Dinitrogen and Carbon Dioxide Activation to Form C-N Bonds at Room Temperature: A New Mechanism Revealed by Experimental and Theoretical Studies.

In light of the current energy requirements, the conversion of CO and N into useful C-N bond-containing products under mild conditions has become an area of intense research. However, the inert nature of N and CO renders their coupling extremely challenging. Herein, nitrogen and carbon atoms originating from N and CO, respectively, are fixed sequentially by NbH anions in the gas phase at room temperature.

The sequential activation of H and N mediated by the gas-phase ScN clusters: Formation of amido unit.

The activation and hydrogenation of nitrogen are central in industry and in nature. Through a combination of mass spectrometry and quantum chemical calculations, this work reports an interesting result that scandium nitride cations ScN can activate sequentially H and N, and an amido unit (NH) is formed based on density functional theory calculations, which is one of the inevitable intermediates in the N reduction reactions. If the activation step is reversed, i.

Oxidation of isoprene by titanium oxide cluster cations in the gas phase.

The heterogeneous oxidation of isoprene (C5H8) by metal-oxide particles, such as the typical mineral aerosols TiO2, plays an important role in the isoprene atmospheric chemistry. However, the underlying mechanism of C5H8 oxidation remains elusive owing to the complexities of aerosol surfaces and reaction channels. Herein, we report the gas-phase reactions of TixOy+ (x = 1-7, y = 1-14) cations with isoprene by using mass spectrometry and density functional theory (DFT) calculations.

NbBN cluster anions reduce four carbon dioxide molecules: reactivity enhancement by ligands.

The thermal gas-phase reactions of Nb2BN2- cluster anions with carbon dioxide have been explored by using the art of time-of-flight mass spectrometry and density functional theory calculations. Four CO2 molecules can be consecutively reduced by Nb2BN2-, resulting in the formation of Nb2BN2O1-4- anions and the release of one CO molecule each time. To illustrate the role of ligands in Nb2BN2-, the reactivities of Nb2N2- and Nb2B- toward CO2 were also investigated; two and three CO2 molecules are activated, respectively, and the rate constants are slower than that of Nb2BN2-/CO2 systems.

Evaporation of mixed citric acid/(NH)SO/HO particles: Volatility of organic aerosol by using optical tweezers.

The condensation and evaporation processes of semi-volatile organic compounds (SVOCs) in atmospheric aerosols can induce significant evolutions of their chemical and physical properties. Hence, for interpreting and predicting composition changes of atmospheric aerosols, it is indispensable to provide insight into the partitioning behaviors of SVOCs between condensed and gas phases. In this research, optical tweezers coupled with cavity-enhanced Raman spectroscopy were employed to observe the volatility of internally mixed citric acid (CA)/(NH)SO (AS) particles, and the effect of AS on the gas/particle partitioning behaviors of atmospheric organic acids was investigated.

Heterogeneous reactions of isoprene and ozone on α-AlO: The suppression effect of relative humidity.

The heterogeneous reactions of α-AlO particles with a mixture of ozone (∼50 ppm) and isoprene (∼50 ppm) were studied as a function of relative humidities (RHs). The reactions were monitored in real time through the microscopic Fourier transform infrared (micro-FTIR) spectrometer. The results show that the presence of ozone leads to the rapid conversion of isoprene to carboxylate (COO) ions on the surfaces of α-AlO particles in the initial stage.