{[1.1.1]Cryptand/Imidazole}: A Prototype Composite Kinetic Molecular Device for Automatic NMR Variable pH Reaction Monitoring

Study on the Photoluminescent and Thermal Properties of Zinc Complexes with a N6O4 Macrocyclic Ligand

“…Macrocyclic and macrobicyclic compounds are attracting increasing attention owing to their interesting structures, properties and important roles in coordination chemistry and many other fields, such as material science and medicinal chemistry [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. With oxygen, nitrogen and/or sulfur donor atoms, these cyclic compounds can exhibit novel electrochemical, photoluminescent and catalytic properties [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 ].…”

Kinetic Buffers

“…[9][10][11][12][13] The small size of the aza cage, synthesized and studied by Lehn and co-workers, [14][15][16] is capable of slowly increasing the pH by 2-3 units over the pH 4-10 range by entrapping H + according to a kinetically controlled process. [9][10][11][12][13] The small size of the aza cage, synthesized and studied by Lehn and co-workers, [14][15][16] is capable of slowly increasing the pH by 2-3 units over the pH 4-10 range by entrapping H + according to a kinetically controlled process.…”

“…For example, they can be used for automatic 1 H NMR monitoring by coupling them to a molecular NMR pH meter to form a molecular apparatus, like the one formed by [1.1.1]cryptand and imidazole, which was recently used for the automatic NMR titration of the organometallic complex [h 6 (C 6 Me 6 )Ru II (bpy)(H 2 O)] 2 + (bpy = 2,2'-bipyridine); [12] this is a cooperative composite KMD, in which more devices work together, without interacting with each other, for the same target. For example, they can be used for automatic 1 H NMR monitoring by coupling them to a molecular NMR pH meter to form a molecular apparatus, like the one formed by [1.1.1]cryptand and imidazole, which was recently used for the automatic NMR titration of the organometallic complex [h 6 (C 6 Me 6 )Ru II (bpy)(H 2 O)] 2 + (bpy = 2,2'-bipyridine); [12] this is a cooperative composite KMD, in which more devices work together, without interacting with each other, for the same target.…”

“…[9][10][11][12][13] The small size of the aza cage, synthesized and studied by Lehn and co-workers, [14][15][16] is capable of slowly increasing the pH by 2-3 units over the pH 4-10 range by entrapping H + according to a kinetically controlled process. This system has been used to carry out spectrophotometric [10,11] and automatic nuclear magnetic resonance (NMR) titrations [12] as well as VpH kinetic experiments [9] as an alternative to a macroscopic autoburette. In these experiments, the instrumental profiles obtained under VpH conditions were fitted to Equations (1) or (2): to obtain 1) the dependence of the rate constant on the pH and 2) the acidity constant, respectively…”

“…The most intriguing aspect of these new devices is the possibility to couple them to other chemical systems (devices or not, pH-sensitive or not). For example, they can be used for automatic 1 H NMR monitoring by coupling them to a molecular NMR pH meter to form a molecular apparatus, like the one formed by [1.1.1]cryptand and imidazole, which was recently used for the automatic NMR titration of the organometallic complex [h 6 (C 6 Me 6 )Ru II (bpy)(H 2 O)] 2 + (bpy = 2,2'-bipyridine); [12] this is a cooperative composite KMD, in which more devices work together, without interacting with each other, for the same target. [11] They can be coupled to pH-sensitive systems that are able to perform work under the stimulus of pH variation.…”