Macropolycyclic ligands containing appropriate binding sites and cavities of suitable size and shape, may be designed so as to display molecular recognition in the formation of selective inclusion complexes, cryptates, with metal cations, but also with anions and molecules. Macrobicyclic ligands B form highly stable and selective alkali and alkaline-earth cryptates, displaying a pronounced cryp...

The dissociation of prototypical metal-cationized amino acid complexes, namely, alkaliated alanine ([Ala+M]+, M+ = Li+, Na+, K+), was studied by energy-resolved tandem mass spectrometry with an ion-trap mass analyzer and by density functional theory. Dissociation leads to formation of fragment ions arising from the loss of small neutrals, such as H2O, CO, NH3, (CO+NH3), and the formation of Na+...

The electrochemical reduction of CO2 is known to be influenced by the identity of the alkali metal cation in the electrolyte; however, a satisfactory explanation for this phenomenon has not been developed. Here we present the results of experimental and theoretical studies aimed at elucidating the effects of electrolyte cation size on the intrinsic activity and selectivity of metal catalysts fo...

Using alkali-metal cation-substituted zeolites and 2,4,6-trihydroxyacetophenone (THAP), which is a typical organic matrix molecule for matrix-assisted laser desorption ionization (MALDI), mass spectrometry has been performed for maltohexaose and acetylsalicylic acid, and the cation-selective ionization of these analytes was achieved. It is found that a complex of cation-substituted zeolite and ...

Different alkali metal atoms are observed to donate electrons to CF(3)Br molecules that are oriented in space. For collision energies high enough to overcome the Coulomb attraction, a positive ion/negative ion pair is observed and mass-analyzed using coincident time-of-flight mass spectroscopy. The alkali metal cation and various negative ions are observed. The most abundant negative ion is the...

The synthesis and cation-binding properties of a series of Calixarene derivatives possessing alkyl chain groups, ester groups and crown ether rings have been investigated. The syntheses of Calix[4]arene crown ethers and Calix[6]arene derivatives possessing alkyl chain, ester group and crown ether ring have been described. In order to evaluate their monovalent cation binding abilities, solvent e...

The iron-molybdenum cofactor of nitrogenase has unprecedented coordination chemistry, including a high-spin iron cluster called the iron-molybdenum cofactor (FeMoco). Thus, understanding the mechanism of nitrogenase challenges coordination chemists to understand the fundamental N2 chemistry of high-spin iron sites. This Account summarizes a series of studies in which we have synthesized a numbe...

Electrode potential measurements have been applied to study electrical characteristics like transport numbers, permselectivity & fixed charged density of zirconium phosphoborate ion exchange membranes. The potential measurements were made across the cation exchange membrane maintained at 27±0.1 °C, using halide and nitrate salts of alkali and alkaline earth metals as electrolytes. The membrane ...

Sixteen lipophilic N-(X)sulfonyl carbamoyl lariat ethers with polyether ring sizes of 12-crown-4, 14-crown-4, 15-crown-5, and 18-crown-6 are utilized for competitive alkali metal cation extractions from aqueous solutions into chloroform. Variation of the electron-withdrawing properties of X in the series of methyl, phenyl, 4-nitrophenyl, and trifluoromethyl allows the influence of the acidity o...