Quantitative elucidation of macrocyclic effect on extraction-ability and -selectivity. Benzo-18-crown-6 and its open-ring analog 1,2-bis[2-(2-methoxyethoxy)ethoxy]benzene–alkali metal picrate systems

Molecular Structures and Stability Constants of Gossypol and Its Aza-Derivative Complexes with Silver(I) Cations Studied by Potentiometric, ESI MS, NMR, and AM1d Semiempirical Methods

“…In summary we can conclude that the highest energetic profits of Ag + complexation by G8−G10 can be explained by the high number of atoms that coordinate the metal cation (from four to six) and by the formation of almost regular octahedral or tetrahedral coordination spheres for the Ag + cation in the structures of the complexes studied. The relatively high stability of the Ag 2 L 2+ complexes formed between gossypol aza-derivatives containing crown-ethers (G7 and G8) and Ag + cations is concerned with the well-known macrocycle effect. − In the structure of G1−G7 complexes the coordination of the Ag + cations is realized mainly by three (in the G4 complex) donor atoms and the coordination sphere of the metal cation is irregular, allowing for the interaction between the metal cation and the solvent; therefore the stability of these complexes is lower. The importance of the coordination sphere geometry becomes apparent in the case of G6−Ag + complexes.…”

Correlation of Solute Transfer Into Toluene and Ethylbenzene from Water and from the Gas Phase Based on the Abraham Model

“…Several published papers reported experimental partition coefficient data for substituted phenols [114][115][116][117][118][119][120][121][122], substituted benzenediols [123], substituted anilines [124,125] and a few miscellaneous organic compounds [126][127][128][129][130][131][132][133][134][135][136][137][138][139]. These latter values pertain to practical partitioning studies where the aqueous and ethylbenzene (or toluene) phases were in direct contact with each other.…”

Partition of compounds from water and from air into the wet and dry monohalobenzenes

“…The experimental data for partitioning from water into the wet halobenzenes are observed partition coefficients, P s , as listed in the Medicinal Chemistry Project database, 22 and also as obtained by Takeda et al, [1][2][3][4][5][6] who have studied a number of crown ethers. These water to wet halobenzene partition coefficients can be converted into air to wet halobenzene partition coefficients, K s , through eqn (1), where K w is the air to water partition coefficient.…”

“…In view of our assessment of solubilities in dry and wet chlorobenzene, below, we included this single data point to give a total of 18 solutes for transfer to dry and wet fluorobenzene. Although this is far too small a number of data points for a five parameter equation, we applied eqn (3) and (4) to yield the LFERs, eqn ( 5) and ( 6); in eqn (5) In eqn ( 5) and ( 6), N is the number of data points (the number of compounds), R is the correlation coefficient, SD is the regression standard deviation, and F is the F-statistic. The leave-one-out statistics are Q 2 , PRESS, and PSD the 'predictive' standard deviation.…”

“…The halobenzenes, especially chlorobenzene and to a lesser extent bromobenzene, are important extraction agents and have been used particularly for the extraction of ligands and ligand-cationic complexes. [1][2][3][4][5][6] In spite of their importance, there has been comparatively little work on the factors that influence partition from water to the halobenzenes. Of the general studies of partitioning from water to organic solvents, [7][8][9][10][11][12][13] that of Marcus 7 deals with 36 compounds into chlorobenzene and 28 into bromobenzene, Meyer and Maurer 9 use only 20 compounds into chlorobenzene, 15 into bromobenzene and 12 into iodobenzene.…”