Cu(II)–N6-Alkyladenine Complexes: Synthesis, X-ray Characterization and Magnetic Properties
María Soledad Martínez,Antonio Bauzá,Amparo Caubet,Angel García-Raso,Angel Terrón,Juan J. Fiol,Elies Molins,Miquel Barceló-Oliver,Antonio Frontera +8 more
TLDR
In this article, three dinuclear copper(II) complexes were synthesized and structurally characterized by single-crystal X-ray diffraction, where HLx, HL2, HL3 are N6-alkyl bidentate NN donor adenine bases.Abstract:
Three new dinuclear copper(II) complexes [Cu2(μ–HLn)2(μ-Cl)2Cl2]Cl2 (1–3) have been synthesized and structurally characterized by single-crystal X-ray diffraction, where HLx, (HL1 = N6-propyladeninium, HL2 = N6-butyladeninium and HL3 = N6-isobutyladeninium) are N6-alkyl bidentate NN donor adenine bases. Complexes 1–3 exhibit a coplanar arrangement of both N6-alkyladeninium moieties with UD conformation, with the terms U(up) or D(down) referring to the coordination of each pyrimidinic N3 atoms to the upper or lower metal center. In the three complexes, both copper atoms are five-coordinated (N2Cl3 donor set), resembling a compressed trigonal bipyramid. Each adenine moiety is protonated in N1 and the positive charge balanced by chloride counterions. Magnetic measurements of complexes 1 and 3 in the 2–300 K temperature range indicate antiferromagnetic coupling with J = −156.1(7) and J = −151(2) cm−1, respectively. Density functional theory calculations have also been performed in order to estimate the exchange coupling constants in these complexes. The theoretically calculated J values are in good agreement with the experimental values.read more
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Synthesis, X‐ray characterization and density functional theory studies of N6‐benzyl‐N6‐methyladenine–M(II) complexes (M = Zn, Cd): The prominent role of π–π, C–H···π and anion–π interactions
Roser Pons,Cristina Ibáñez,Ana B. Buades,Antonio Franconetti,Angel García-Raso,Juan J. Fiol,Angel Terrón,Elies Molins,Antonio Frontera +8 more
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Crystal structures of N6-modified-aminoacid/peptide nucleobase analogs: hybrid adenine–glycine and adenine–glycylglycine molecules
Angel García-Raso,Angel Terrón,Antonio Bauzá,Antonio Frontera,Jhon jairo Molina,Ezequiel M. Vázquez-López,Juan J. Fiol +6 more
TL;DR: In this paper, the synthesis and X-ray characterization of three N6-aminoacid/peptide-adenine-derivatives; the zwitterion N6GlyAde·0.5H2O (1), its corresponding protonated form N6 GlyAdE·2HCl·H 2O (2) and N6 glyGly Ade·H2 O (3).
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