Supporting Information Available

Mononuclear copper(II) complexes of bis-triazole-based macrocyclic Schiff base hydrazones; direct synthesis, EPR studies, magnetic and thermal properties

Hamid Khanmohammadi,*[a] Malihe Erfantalab,[a] and Edward J. Reijerse [b]

[a] Department of Chemistry, Arak University, Arak, 38156-8-8349, Iran

[b]Max Planck Institute for Chemical Energy Conversion,Mülheim an der Ruhr, Germany

Contents

I. Materials and General Procedures………………….………………………………………… S1

II. Physical Measurements ……..…………………….…………………………………………. S1

III. Syntheses ………………………………...…………………………………………………. S2

  1. 1H NMR and IR spectra of I and II……….………………………...………..…..……… S3, S4

V. IR and Uv-vis spectra of III and IV...…………..………………………………………... S5, S6

VI. Additional thermal analysis …………………………………………………...…………... S7

VII. XRD spectra of Complex III and IV ………………...……………………….………….. S8

VIII. EPR spectra of aggregation of copper complex III……..…………………..……...….. S9

IX. Simulation ESI mass spectra of copper complexes ……………………………..…….. S9, S10

X. References…………………………………..………………….………..…………………. S11

  1. Materials and General Procedures

All chemicals and solvents were of reagent grade and purchased commercially. 4-amino-3-(4-pyridyl)-5-mercapto-1,2,4-triazole [1], N,N'-ethylene-bis(3-formyl-5-methylsalicylaldimino)copper(II), CuL, [2] and bis(4-amino-1,2,4-triazolepyridylsulfanyl)ethane, I, [3] were prepared as described previously.

  1. Physical Measurements

1H NMR spectra was obtained with a Bruker Avance 300 MHz spectrometer. Electronic spectral measurements were carried out using a Perkin-Elmer Lambda spectrophotometer in the range 200-600 nm. Thermal analyses were performed on a Perkin-Elmer Thermogravimetric Analyzer TG/DTA 6300 instrument. Elemental analyses were performed on an Elementar Vario EL III elemental analyzer. Infrared spectra were recorded as pressed KBr discs, using a Unicam Galaxy Series FT-IR 5000 spectrophotometer (400-4000 cm-1). Electron Paramagnetic Resonance (EPR) was obtained from frozen solutions at 10-50 K with a Bruker ELEXSYS E500 spectrometer operating at X-band utilizing microwave frequencies around 9.5 GHz. The concentrations of copper complexes were in range of 1×10-4 M - 2×10-3 M in DMSO and DMF solvents. The g║, g, A║, and A┴ were evaluated using Easy Spin software [4]. The variable temperature magnetic measurements were undertaken in a superconducting quantum interference device (SQUID) in the range (2-290 K)and the data were simulated by julX[5]. The positive electrospray mass spectra (ESI-MS) in DMF:Methanol (50:50) solutions were recorded on a Q-ToF Ultima, Waters apparatus. Electrochemical measurements were recorded on an Autolab 30V potentiostat/Galvanostat of Eco Chemical Company. All readings were taken using a three electrode potentiostatic system in DMSO with 0.1 mol cm-3 tetrabutylammonium perchlorate (TBAP, electrochemical grade, Acros) as supporting electrolyte. A three-electrode assembly composed of a glassy carbon working electrode, a platinum auxiliary electrode, and Ag-AgCl reference electrode was used with sample concentrations of 1×10-3 molcm-3. X-ray diffraction studies were performed in a X-Pert PW 3710 powder diffractometer with Cu-Kα radiation (1.5406 Å) at 40 kV and 35 mA current.

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III. Syntheses

Synthesis of bis(4-amino-1,2,4-triazolepyridylsulfanyl)1,3-methylbenzene, II

To a solution of 4-amino-3-(4-pyridyl)-5-mercapto-1,2,4-triazole (0.386 g, 2 mmol) in ethanol (50 mL) containing KOH (0.112 g, 2 mmol) was added 1,3-bis(bromomethyl)benzene (0.264 g, 1 mmol). The reaction mixture was heated under reflux for 1 h. The solvent was removed in vacuum and the remaining solid was collected and washed with water.

Yield: 81%, m.p. = 208-209 oC. 1H NMR(d6-DMSO, ppm): 8.72(dd, 4H, J= 6.00 Hz), 7.98(dd, 4H,J=6.00 Hz), 7.56(s, br, 1H), 7.29(m, 3H), 6.23(s, 4H), 4.46(s, 4H). IR (KBr, cm-1); IR (KBr, cm-1); 3340, 3267 υ(NH2),1602υ(C=C), 1556 υ(C=C-N), 1232 υ(N-N), 825 υ(NCN). Anal.Calcd. for C22H20N10S2: C, 54.08; H, 4.13; N, 28.67; S, 13.13.Found: C, 54.23; H, 4.28; N, 28.34; S, 13.01.

General procedure for the synthesis of Copper(II) complexes, III and IV

A solution of diamine, I and/or II, (1 mmol) in MeOH: CH3COOH (5:1) solution, 5 mL, was added to a suspension of N, N'- ethylene-bis(3-formyl-5-methylsalicylaldimino)copper(II) (1 mmol) and copper perchlorate (1 mmol) in methanol (15 mL) at 60 ºC. The mixture was heated for 15-17 h at same temperature. The isolated green solid was filtered and washed well with warm absolute methanol.

Complex III

The isolated green solid was crystallized from DMF. IR (KBr, cm-1); 1652(shoulder), 1637υ(C=N), 1606, 1572, 1539, 1448, 1383, 1309, 1236, 991, 831, 705, 684, 586, 509. UV-Vis λmax(nm)(ε (M-1cm-1)) in DMF: 275(49967), 419(22077), 596(1333). Anal. Calc. for C36H30N12O2S2Cu. 0.5 DMF: C, 54.47; H, 4.08; N, 21.17; S, 7.76; Cu, 7.69 %. Found: C, 54.61; H, 4.43; N, 21.17; S, 7.71; Cu, 7.94 %. g║= 2.23, A║= 560× 10-4 cm-1. μeff = 2.00 ± 0.05 BM.

Complex IV

S2

IR (KBr, cm-1); 1637υ(C=N), 1602, 1574, 1541, 1446, 1379, 1307, 1234, 1091, 991, 775, 696, 623, 584, 513. UV-Vis λmax(nm)(ε (M-1cm-1)) in DMSO: 275(69165), 423(30000), 607(1500). Anal. Calc. for C42H34N12O2S2Cu. 0.5 CH3OH: C, 57.84; H, 4.11; N, 19.05; S, 7.27; Cu, 7.20 %. Found: C, 57.80; H, 4.43; N, 18.62; S, 7.10; Cu, 7.14 %. g║= 2.23, A║=500× 10-4 cm-1. μeff= 1.99 ± 0.05 BM.

  1. 1H NMR and IR spectra of I and II

Figure S1. 1H NMR and IR spectra of I

S3

Figure S2. 1H NMR and IR spectra of II

S4

V. IR andUv-visspectra of III and IV

Figure S3. IR and Uv-vis spectra of III

S5

Figure S4. IR and Uv-vis spectra of IV

S6

VI.Additional thermal analysis

Figure S5. TGA-DTA analyses curve of III

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VII.XRD spectra of Complex III and IV

Figure S6. XRD spectra of Complex III

Figure S7. XRD spectra of Complex IV

S8

VIII.EPR spectra of aggregation of copper complex III

Figure S8. The time dependent EPR spectra of III copper complex in DMSO and DMF solvents.

IX.Simulation ESI mass spectra of copper complexes

S9

Figure S9. Simulation ESI-MS(+) of complex III

S10

Figure S10. Simulation ESI-MS(+) of complex III

X. References

(1)Reid, J. R.; Heindel, N. D. J. Heterocycl. chem.1976,13, 925.

(2)Ōkawa, H.; Kida, S. Bull. Chem. Soc. Jpn. 1972, 45, 1759.

(3)A. Abbas, Tetrahedron2004, 60, 1541.

(4)Stoll, S.; Schweiger, A. J. Magn. Reson.2006, 178(1), 42.

(5)E. Bill,

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