The Chemistry of 1,4,7‐Triazacyclononane and Related Tridentate Macrocyclic Compounds

Improved Synthesis and Detailed Characterization of a Hybrid Pyrazole‐TACN Dinucleating Ligand

“…This is evident from the significant shift in resonance of one of the four isopropyl groups in the 1 H NMR spectra. The observation of four weak quaternary signals in the downfield region of the corresponding 13 C NMR spectra (δ = 130-170 ppm, Figures S2 and S4, Supporting Information) reveals asymmetry with respect to the pyrazole unit and, taken together with the relatively sharp 1 H NMR resonances at approximately δ = 13 ppm, indicates that the acidic pyrazole-NH proton is once again localized. Dissolution in CD 3 OD renders the pyrazole ring symmetric by restoring the proton tautomerization, although the observation of two sets of aliphatic signals indicates that the two halves of each macrocyclic side arm remain inequivalent, due to the high rotational barrier of the amide bond ( Figures S5 and S6, Supporting Information).…”

“…[1][2][3] This macrocycle and its related derivatives have thus found widespread application in the fields of organometallic, bioinorganic, and coordination chemistry. [2][3][4][5][6][7][8] Covalently tethering two of these prominent TACN units using an appropriate linker can provide expanded ligand analogues tailored for the preparation of dinuclear complexes.…”

Fluorescent and Electrochemical Sensing of Polyphosphate Nucleotides by Ferrocene Functionalised with Two ZnII(TACN)(pyrene) Complexes

“…[12] Binding of one TACN macrocycle to a metal ion generally leaves one or more coordination sites occupied by weakly binding lig-A C H T U N G T R E N N U N G ands (e.g., solvent molecules, halides) that can be displaced by ligands with a higher affinity for that particular metal ion. For example, in the case of Cu II A C H T U N G T R E N N U N G (TACN) and Zn II -A C H T U N G T R E N N U N G (TACN) complexes, the phosphate anions in DNA/RNA sequences have been shown to displace such weakly binding ligands.…”

Binding and Structural Aspects of Nitrile- and Amino-Functionalised Pendant Arm Derivatives of 1,4,7-Triazacyclononane ([9]aneN3)

“…The synthesis, structure, and coordination properties of [9]aneN 3 and other polyazamacrocycles bearing N-attached coordinating pendant groups have been reviewed [1,[8][9][10]40]. The present review covers the last four years of our work in this field and is only focussed on synthetic aspects and coordination properties of nitrile-and aminofunctionalised pendant arms derivatives of [9]aneN 3 .…”

“…The coordination chemistry of the tridentate macrocycle 1,4,7-triazacyclononane ( [9]aneN 3 ) and its N-alkylated analogues (R 3 - [9]aneN 3 ) with main group and transition metal ions has been comprehensively studied over the last thirty years [1][2][3][4][5][6][7]. In addition to kinetically inert and thermodynamically stable sandwich complexes, a series of polynuclear complexes have also been prepared in the presence of suitable bridging ligands.…”