On Assembling Polychlorinated Aromatic Hydrocarbons from Carbon Tetrachloride via Dichlorocarbene Intermediary by A Solvothermal Reaction: A Reaction Pattern from Carbene−Ylide Interconversion.

On Assembling Polychlorinated Aromatic Hydrocarbons from Carbon Tetrachloride via Dichlorocarbene Intermediary by A Solvothermal Reaction:  A Reaction Pattern from Carbene−Ylide Interconversion

On Assembling Polychlorinated Aromatic Hydrocarbons from Carbon Tetrachloride via Dichlorocarbene Intermediary by a Solvothermal Reaction: A Reaction Pattern from Carbene−Ylide Interconversion

The forced one-electron reduction of carbon tetrachloride with sodium in a sealed steel vessel is shown to have a narrow window of conditions to arrest the reaction at the polychlorinated aromatic hydrocarbons (PCAHs), as well as to prevent the reaction from proceeding all the way to the final stage of graphite and other carbon solids. The intermediates are quenched with toluene or benzene to give electrophilic substitution products and with water to give a quinomethine as the major product. The product pattern leads us to propose the carbene, perchlorobenzo[c,d]pyren-6-ylidene, or its reversible dimer as the major intermediate among others, that survives the severe conditions until coming into contact with these nucleophiles. Mainly from aromatic resonance stabilization, the carbene is proposed to have a delocalized singlet state analogous to a ylide electronic structure and, thus, undergoes observed ionic reactions instead of typical carbene reactions. This work serves as a mechanistic link on the structural evolution of carbon networks between molecular chemistry and nanomaterial chemistry

On Assembling Polychlorinated Aromatic Hydrocarbons from Carbon Tetrachloride via Dichlorocarbene Intermediary by A Solvothermal Reaction: A Reaction Pattern from Carbene−Ylide Interconversion.

On Assembling Polychlorinated Aromatic Hydrocarbons from Carbon Tetrachloride via Dichlorocarbene Intermediary by A Solvothermal Reaction:  A Reaction Pattern from Carbene−Ylide Interconversion

Real-Time Sniffing Mass Spectrometry Aided by Venturi Self-Pumping Applicable to Gaseous and Solid Surface Analysis

Based on the Venturi self-pumping effect, real-time sniffing with mass spectrometry (R-sniffing MS) is developed as a tool for direct and real-time mass spectrometric analysis of both gaseous and solid samples. It is capable of dual-mode operation in either gaseous or solid phase, with the corresponding techniques termed as Rg-sniffing MS and Rs-sniffing MS, respectively. In its gaseous mode, Rg-sniffing MS is capable of analyzing a gaseous mixture with response time (0.8–2.1 s rise time and 7.3–9.6 s fall time), spatial resolution (<80 μm), three-dimensional diffusion imaging, and aroma distribution imaging of red pepper. In its solid mode, an appropriate solvent droplet desorbs the sample from a solid surface, followed by the aspiration of the mixture using the Venturi self-pumping effect into the mass spectrometer, wherein it is ionized by a standard ion source. Compared with the desorption electrospray ionization (DESI) technique, Rs-sniffing MS demonstrated considerably improved limit of detection (LOD) values for arginine (0.07 μg/cm2 Rs-sniffing vs 1.47 μg/cm2 DESI), thymopentin (0.10 μg/cm2vs 2.67 μg/cm2), and bacitracin (0.16 μg/cm2vs 2.28 μg/cm2). Rs-sniffing is applicable for the detection of C60(OCH3)6Cl–, an intermediate in the methoxylation reaction involving C60Cl6 (solid) and methanol (liquid). The convenient and highly sensitive R-sniffing MS has a characteristic separation of desorption from the ionization process, in which the matrix atmosphere of desorption can be interfaced by a pipe channel and self-pumped by the Venturi effect with consequent integration using a standard ion source. The R-sniffing MS operates in a voltage-, heat-, and vibration-free environment, wherein the analyte is ionized by a standard ion source. Consequently, a wide range of samples can be analyzed simultaneously by the R-sniffing MS technique, regardless of their physical state

C₇₂Cl₄: A Pristine Fullerene with Favorable Pentagon-Adjacent Structure

A long-sought empty non-IPR fullerene, #11188C72, which is more stable than the sole IPR isomer in the fullerene[72] family, has been retrieved and crystallographically characterized as #11188C72Cl4. Mass spectrometric data support the facile dechlorination of #11188C72Cl4 and, in turn, the possible stability of pristine #11188C72

C₇₆Cl₃₄: High Chlorination of the Inherent Chiral Fullerene with a Helical Configuration

As the smallest chiral fullerene in conformity with the Isolated Pentagon Rule (IPR), D2-symmetric C76 has been chlorinated with iodine monochloride to form C76Cl34, a highly chlorinated derivative. Its structure with the chiral cage enwrapped by a helical chlorine pattern has been established using single-crystal X-ray diffraction analysis. The high chlorination and its implication for constructing novel chiral fullerene-based materials are discussed

C₇₂Cl₄: A Pristine Fullerene with Favorable Pentagon-Adjacent Structure

A long-sought empty non-IPR fullerene, #11188C72, which is more stable than the sole IPR isomer in the fullerene[72] family, has been retrieved and crystallographically characterized as #11188C72Cl4. Mass spectrometric data support the facile dechlorination of #11188C72Cl4 and, in turn, the possible stability of pristine #11188C72

C₇₆Cl₃₄: High Chlorination of the Inherent Chiral Fullerene with a Helical Configuration

As the smallest chiral fullerene in conformity with the Isolated Pentagon Rule (IPR), D2-symmetric C76 has been chlorinated with iodine monochloride to form C76Cl34, a highly chlorinated derivative. Its structure with the chiral cage enwrapped by a helical chlorine pattern has been established using single-crystal X-ray diffraction analysis. The high chlorination and its implication for constructing novel chiral fullerene-based materials are discussed

pH-Induced Simultaneous Synthesis and Self-Assembly of 3D Layered β-FeOOH Nanorods

Higher-ordered architectures self-assembly of nanomaterials have recently attracted increasing attention. In this work, we report a spontaneous and efficient route to simultaneous synthesis and self-assembly of 3D layered β-FeOOH nanorods depending on a pH-induced strategy, in which the continuous change of pH is achieved by hydrolysis of FeCl3·6H2O in the presence of urea under hydrothermal conditions. The electron microscopy observations reveal that the square-prismic β-FeOOH nanorods are self-assembled in a side-by-side fashion to form highly oriented 2D nanorod arrays, and the 2D nanorod arrays are further stacked in a face-to-face fashion to form the final 3D layered architectures. On the basis of time-dependent experiments, a multistage reaction mechanism for the formation of the 3D layered β-FeOOH nanorods architecture is presented, involving the fast growth and synchronous self-assembly of the nanorods toward 1D, 2D, and 3D spontaneously. The experimental evidence further demonstrates that the urea-decomposition-dependent pH continuously changing in the solution, spontaneously altering the driving force competition between the electrostatic repulsive force and the attractive van der Waals force among the nanorods building blocks, is the essential factor to influence the self-assembly of the β-FeOOH nanorods from 1D to 3D

Probing Hydrogen Bond Energies by Mass Spectrometry

Mass spectrometry with desorption electrospray ionization (DESI) is demonstrated to be useful for probing the strength of hydrogen bonding, exemplified by various complexes of benzothiazoles and carboxylic acids in the solid state. Efficiencies for fragmentation of the complexes, quantified by collision-induced dissociation (CID) technology, correspond well with energies of the hydrogen bonds of O–H···N and N–H···O bridging each pair of benzothiazole and carboxylic acid. Linear correlations (with correlation factors of 0.8953 and 0.9928) have been established for the calibration curves of normalized collision energy at 100% fragmentation rate vs the length between donor and acceptor (in the hydrogen bond of O–H···N) as well as the slope of the fragmentation efficiency curve vs the average length difference between O–H···N and N–H···O in the complex. The mechanism responsible for determination of the hydrogen bonds is proposed on the basis of the experiments starting from the mixtures of the complexes as well as labeling with deuterium. As a complement of previously available methods (e.g., X-ray diffraction analysis), expectably, the proposed mass spectrometric method seems to be versatile for probing hydrogen bond energies