Copper(II) Complexes with 4-Amino-<i>N</i>-[4,6-dimethyl-2-pyrimidinyl]benzenesulfonamide.
Synthesis, Crystal Structure, Magnetic Properties, EPR, and Theoretical Studies of a Novel
Mixed μ-Carboxylato, NCN-Bridged Dinuclear Copper Compound
L. Gutiérrez
G. Alzuet
J. Borrás
A. Castiñeiras
A. Rodríguez-Fortea
E. Ruiz
10.1021/ic000869i.s001
https://acs.figshare.com/articles/journal_contribution/Copper_II_Complexes_with_4-Amino-_i_N_i_-_4_6-dimethyl-2-pyrimidinyl_benzenesulfonamide_Synthesis_Crystal_Structure_Magnetic_Properties_EPR_and_Theoretical_Studies_of_a_Novel_Mixed_-Carboxylato_NCN-Bridged_Dinuclear_Copper_Compound/3600738
New Cu(II) complexes of sulfamethazine (4-amino-<i>N</i>-[4,6-dimethyl-2-pyrimidinyl]benzenesulfonamide, HL)
[Cu<sub>2</sub>(CH<sub>3</sub>COO)<sub>2</sub>(L)<sub>2</sub>]·2dmf (<b>1</b>) and {[Cu(L)<sub>2</sub>]·2H<sub>2</sub>O}<sub>∞</sub> (<b>2</b>) were prepared and structurally characterized. Compound
<b>1</b> crystallizes in the monoclinic system, space group <i>P</i>2<sub>1</sub>/<i>n</i>, with <i>a </i>= 8.9486(9) Å, <i>b </i>= 15.0956(12) Å, <i>c</i> =
16.542(3) Å, <i>β</i> = 105.584(15)°, and <i>Z </i>= 2. Compound <b>2</b> crystallizes in the monoclinic system, space group
<i>P</i>2<sub>1</sub>/<i>c</i>, with <i>a </i>= 13.8097(8) Å, <i>b </i>= 14.5765(4) Å, <i>c</i> = 13.7853(15) Å, <i>β</i> = 96.033(9)°, and <i>Z </i>= 1. In compound
<b>1</b> two copper ions are linked by two syn−syn acetates and two nonlinear NCN bridging groups pertaining to the
deprotonated sulfamethazine ligands. Each copper center presents a nearly square planar geometry. Magnetic
susceptibility data for <b>1</b> show a strong antiferromagnetic coupling with 2<i>J</i> = −216.7 cm<sup>-1</sup>. The EPR spectra at
the X- and Q-band frequencies present the signals corresponding to the dinuclear entity, being the zero-field
splitting parameter, <i>D </i>= 0.265 cm<sup>-1</sup>. The antiferromagnetic exchange coupling is discussed using DFT calculations
on some model compounds with NCN bridging ligands and also on model structures with mixed <i>μ</i>-acetato and
NCN bridges. The copper in the polymeric compound <b>2</b> is five coordinate. The CuN<sub>5</sub> chromophore has a highly
distorted square pyramidal geometry with small axial N−Cu−N angles of 65.53(14) and 59.90(13)°. In the structure
a sulfamethazinate anion binds to one copper through the sulfonamido and pyrimidine N atoms and to an adjacent
copper via the amino N atom.
2001-05-19 00:00:00
Crystal Structure
NCN bridges
copper center
EPR spectra
compound 2
2 J
compound 1
0.265 cm
CH 3 COO
HL
Cu 2
Theoretical Studies
antiferromagnetic exchange
1 show
dimethyl
deprotonated sulfamethazine ligands
Magnetic Properties
dinuclear entity
sulfamethazinate anion
nonlinear NCN
2 crystallizes
pyrimidine N atoms
CuN 5 chromophore
copper ions
DFT calculations
Magnetic susceptibility data
model compounds
model structures
N atom
Compound 1 crystallizes