14098-44-3Relevant articles and documents
Izatt et al.
, p. 7626,7627,7628 (1976)
Synthesis and properties of macroheterocyclic azomethines based on 4-aminobenzo-15-crown-5
Sadovskaya, N. Yu.,Glushko,Retivov,Belus',Grokhovskii
, p. 2771 - 2777 (2015)
A number of new stable azomethine crown ether derivatives have been synthesized by condensation of 4-aminobenzo-15-crown-5 with aromatic aldehydes. Complexation of the products with transition metal cations (Cu2+, Zn2+, Fe3+, Co3+, Ni3+) has been studied by spectrophotometry.
Template Effects. 6. The Effect of Alkali Metal Ions on the Formation of Benzo-3x-crown-x Ethers over a Wide Range of Ring Sizes
Mandolini, Luigi,Masci, Bernardo
, p. 168 - 174 (1984)
The rate formation of benzo-3x-crown-x ethers with x = 4,5,7,10 and 16 via intramolecular alkylation of o--OC6H4(OCH2CH2)x-1Br in 99percent aqueous Me2SO was found to be markedly affected by added alkali metal bromides.Catalysis or inhibition was observed, depending on the cation-substrate pair.Combination of the present results with those previously reported for the formation of B18C6 offers a large variety of patterns.The magnitude of the observed effects ranges over four powers of ten.The dependence of the observed rates (kobsd) on metal ion concentration was expessed in terms of independent contributions from free and cation-paired aryl oxide ions, whose relative weights are ruled by the rate constants ki and kip, respectively, and by the ion-pairing association constants KArO-.A self-consistent analysis was used to derive numerical values of the above parameters.A definite contribution from an additional reaction path involving two metal ions was detected in the case of the K+-catalyzed formation of B30C10.The equilibrium constants KC for associations between many cation-crown pairs were also determined under the same conditions.A comparative analysis of structure and metal ion effects on the extent of interaction of the alkali metal ions with the reactants, transition states, and reaction products shows that the cation interaction in the transition state is strongly reminiscent of the host-guest interactions found in the cation-B3XCx complexes.The catalytic efficiency of the alkali metal ioms (log kip/ki) shows a definite tendency to parallel the strength of interaction with the reaction products (log KC), thus indicating that a metal ion capable of binding strongly with a crown ether is also a good catalyst for the formation of the crown ether itself.
Complete charge separation provoked by full cation encapsulation in the radical mono- and di-anions of 5,6:11,12-di-: O -phenylene-tetracene
Wombacher, Tobias,Goddard, Richard,Lehmann, Christian W.,Schneider, J?rg J.
, p. 10874 - 10883 (2018)
Herein, we report the synthesis and molecular structure of the mono- and dianionic aromatic molecules [(B15C5-κ5O)2K+](LDOPT-) (1) and [(B15C5-κ5O)2K+]2(LDOPT2-)THFsolv (2) derived from the parent aromatic polyhydrocarbon 5,6:11,12-di-o-phenylenetetracene (DOPT, LDOPT) by a controlled stepwise one and two electron chemical reduction. The effect of single and double electron charge transfer to a polycondensed aromatic hydrocarbon (PAH) without any disturbing influence of an associated metal cation has been demonstrated. This was achieved by fully sandwiching the cationic K+ counterions between two benzo-15-crown-5-ether (B15C5) ligands resulting in a fully encapsulating (κ10O) geometry which ensures a complete separation of the K+ counterions and the bare anionic PAH species [LDOPT-] and [LDOPT2-]. The structural changes accompanied by the stepwise reduction from LDOPT to [LDOPT-] to [LDOPT2-] are discussed and compared to earlier predictions based on density functional theory (DFT) as well as the results of previous studies of alkaline metal cationic PAH anion interactions of DOPT in which only a partial metal cation encapsulation has been achieved so far.
Structure and Reactivity of Lithium and Sodium Aryloxides in Dimethylformamide. Ions, Ion Pairs, and Ion Triplets
Crescenzi, Manuela,Galli, Carlo,Mandolini, Luigi
, p. 551 - 553 (1986)
Reactivity and u.v. spectra of aryloxide ions in dimethylformamide are affected by the addition of either Li(1+) and Na(1+) ions in a way that suggests the occurrence of ion triplets M(1+)A(1-)M(1+) in addition to free ions and ion pairs.
Novel crown ether functionalized imidazolium-based acidic ionic liquid catalyzed synthesis of pyrazole derivatives under solvent-free conditions
Patil, Dayanand,Chandam, Dattatraya,Mulik, Abhijeet,Jagdale, Suryabala,Patil, Prasad,Deshmukh, Madhukar
, p. 6843 - 6858 (2015/08/18)
Abstract An innovatively designed novel crown ether functionalized imidazolium-based reusable acidic ionic liquid [crown ether MIm] [HSO4] has been efficiently implemented for the synthesis of pyrazole derivatives using various substituted enaminones, hydrazine hydrate and phenyl hydrazine under solvent-free conditions. Structural novelty and task efficiency of the catalyst, high yields of desired products, greener approach attributing high atom economy and solvent-free conditions render this protocol suitable to cope with the current demand in contemporary organic chemistry. The inventive idea of utilizing crown ether functionalized ionic liquid as a catalyst was for the first time demonstrated in this protocol.
