15

Studies of some metal complexes of a Quinoxaline based unsymmetrical ONNO donor ligand: Synthesis, spectral characterization, thermal, in vitro biological and DFT studies

C. Justin Dhanaraj* ∙ Jijo Johnson

Department of Chemistry, University College of Engineering, Nagercoil, Anna University Constituent College, Konam, Nagercoil – 629 004, Tamil Nadu, India

Supplementary data

Fig. S1 IR spectra of L and its metal(II) complexes

Fig. S2 Electronic absorption spectra of a) L, b) [Co(L)], c) [Ni(L)], d) [Cu(L)] and e) [Zn(L)] complex

Fig. S3 1H NMR spectra of a) L and b) [Zn(L)] complex

Fig. S4 13C NMR spectra of a) L and b) [Zn(L)] complex

Fig. S5 Mass spectrum of L

Fig. S6 Mass spectrum of [Zn(L)] complex of L

Fig. S7 X-band EPR spectra of [Cu(L)] complex a) at room temperature and b) at liquid nitrogen temperature

Fig. S8 Powder XRD diffractograms of a) L, b) [Co(L)], c) [Ni(L)], d) [Cu(L)] and e) [Zn(L)] complexes

Fig. S9 Cyclic voltammograms of a) L, b) [Co(L)], c) [Ni(L)] and d) [Zn(L)] complexes

Fig. S10 The cytotoxici effect of a) [Ni(L)], b) [Cu(L)] and c) [Zn(L)] complexes on MCF7 cell line

Fig. S11 Cytotoxic effect of L and its metal(II) complexes on MCF7 cell line at different concentrations.

Table S1 Summary of PXRD and refined parameters of L and its and Cu(II) complex

Parameter / L / [Cu(L)]
Temperature/K / 298 / 298
Method / Microcrystalline / Microcrystalline
Radiation / Cu-Kα1 / Cu-Kα1
Wavelength / 1.54060 / 1.54060
2Ɵ range / 10-80 / 10-80
Unit cell dimension
a/Å / 6.84 / 7.18
b/Å / 9.00 / 8.65
c/Å / 20.80 / 21.40
α/º / 51.60 / 90.00
β/º / 98.41 / 51.32
γ/º / 97.02 / 90.00
Volume/Å3 / 992.84 / 1037.03
Crystal system / Triclinic / Monoclinic
Space group / P-121 / P-121

Table S2. Atomic charges for optimized geometry of L

Atom / Mulliken atomic
charge / Natural atomic charge / Atom / Mulliken atomic
charge / Natural atomic charge
1 C / 0.174888 / 0.1172 / 24 H / 0.097979 / 0.23538
2 C / 0.228858 / 0.09969 / 25 H / 0.121891 / 0.25243
3 C / 0.358985 / 0.17034 / 26 C / -0.054675 / -0.28518
4 C / 0.578231 / 0.61952 / 27 H / 0.110299 / 0.23913
5 H / 0.113197 / 0.259 / 28 H / 0.070931 / 0.19842
6 C / -0.091859 / -0.19547 / 29 N / -0.397524 / -0.42899
7 C / -0.118922 / -0.27432 / 30 C / 0.221553 / 0.28814
8 H / 0.27301 / 0.4413 / 31 C / -0.377675 / -0.75733
9 C / -0.08644 / -0.20481 / 32 H / 0.113879 / 0.2494
10 C / -0.095366 / -0.25864 / 33 H / 0.127322 / 0.24898
11 H / 0.095445 / 0.24398 / 34 H / 0.13286 / 0.25666
12 H / 0.100857 / 0.24815 / 35 C / 0.067951 / -0.12355
13 H / 0.097813 / 0.24877 / 36 C / -0.124333 / -0.21076
14 N / -0.647196 / -0.59055 / 37 C / 0.307881 / 0.35785
15 N / -0.514649 / -0.38902 / 38 C / -0.093239 / -0.26737
16 O / -0.504803 / -0.6021 / 39 H / 0.083566 / 0.23802
17 C / 0.094821 / 0.05844 / 40 C / -0.132489 / -0.31651
18 H / 0.113305 / 0.22466 / 41 C / -0.087052 / -0.21879
19 N / -0.353491 / -0.39553 / 42 H / 0.080664 / 0.23992
20 C / -0.049885 / -0.29272 / 43 H / 0.071804 / 0.23029
21 H / 0.136052 / 0.25827 / 44 H / 0.085404 / 0.24024
22 H / 0.074012 / 0.20293 / 45 O / -0.542025 / -0.67657
23 C / -0.175182 / -0.46789 / 46 H / 0.313345 / 0.489

Table S3. Atomic charges for optimized geometry of [Co(L)] complex

Atom / Mulliken atomic
charge / Natural atomic charge / Atom / Mulliken atomic
charge / Natural atomic charge
1 C / 0.129779 / 0.12062 / 24 H / 0.211557 / 0.27469
2 C / 0.183085 / 0.1073 / 25 C / -0.1045 / -0.27794
3 C / 0.170025 / 0.17029 / 26 H / 0.186766 / 0.24694
4 C / 0.519107 / 0.54249 / 27 H / 0.113021 / 0.23615
5 H / 0.095306 / 0.24421 / 28 N / -0.431175 / -0.43296
6 C / -0.071641 / -0.21188 / 29 C / 0.266584 / 0.36133
7 C / -0.083314 / -0.22676 / 30 C / -0.366831 / -0.72628
8 C / -0.093577 / -0.22246 / 31 H / 0.139553 / 0.25295
9 C / -0.102904 / -0.24534 / 32 H / 0.122689 / 0.24487
10 H / 0.107851 / 0.25178 / 33 H / 0.154721 / 0.26182
11 H / 0.095381 / 0.24046 / 34 C / 0.015607 / -0.16221
12 H / 0.090415 / 0.2389 / 35 C / -0.124183 / -0.21118
13 N / -0.421568 / -0.47537 / 36 C / 0.385326 / 0.34641
14 N / -0.42519 / -0.42059 / 37 C / -0.105098 / -0.26587
15 O / -0.644422 / -0.65957 / 38 H / 0.077884 / 0.23093
16 C / 0.143616 / 0.13311 / 39 C / -0.128314 / -0.27283
17 H / 0.130271 / 0.22315 / 40 C / -0.070277 / -0.20464
18 N / -0.464306 / -0.49496 / 41 H / 0.078822 / 0.2358
19 C / -0.049375 / -0.32262 / 42 H / 0.108594 / 0.25444
20 H / 0.156575 / 0.28024 / 43 H / 0.088851 / 0.23875
21 H / 0.132285 / 0.27333 / 44 O / -0.650662 / -0.61386
22 C / -0.223944 / -0.48477 / 45 Co / 0.536953 / 0.65808
23 H / 0.120656 / 0.26303 / ------

Table S4. Atomic charges for optimized geometry of [Ni(L)] complex

Atom / Mulliken atomic
charge / Natural atomic charge / Atom / Mulliken atomic
charge / Natural atomic charge
1 C / 0.128974 / 0.12306 / 24 H / 0.205916 / 0.27502
2 C / 0.183344 / 0.10845 / 25 C / -0.102578 / -0.27616
3 C / 0.169643 / 0.17031 / 26 H / 0.187629 / 0.24664
4 C / 0.520978 / 0.54373 / 27 H / 0.113144 / 0.23583
5 H / 0.095773 / 0.24446 / 28 N / -0.440257 / -0.46353
6 C / -0.071395 / -0.21171 / 29 C / 0.261971 / 0.36542
7 C / -0.083179 / -0.22651 / 30 C / -0.367069 / -0.72729
8 C / -0.093371 / -0.22215 / 31 H / 0.138269 / 0.25209
9 C / -0.102633 / -0.24476 / 32 H / 0.122269 / 0.24471
10 H / 0.10815 / 0.25194 / 33 H / 0.153997 / 0.26141
11 H / 0.095643 / 0.24057 / 34 C / 0.022303 / -0.15504
12 H / 0.090769 / 0.23905 / 35 C / -0.124812 / -0.2125
13 N / -0.417399 / -0.473 / 36 C / 0.387509 / 0.35061
14 N / -0.423421 / -0.42031 / 37 C / -0.103321 / -0.26176
15 O / -0.626659 / -0.65285 / 38 H / 0.07846 / 0.23122
16 C / 0.148289 / 0.14468 / 39 C / -0.126046 / -0.27013
17 H / 0.13104 / 0.22301 / 40 C / -0.071232 / -0.20637
18 N / -0.465348 / -0.51995 / 41 H / 0.079712 / 0.23603
19 C / -0.056273 / -0.32298 / 42 H / 0.108945 / 0.25443
20 H / 0.15576 / 0.27857 / 43 H / 0.089005 / 0.23881
21 H / 0.129127 / 0.27107 / 44 O / -0.627013 / -0.59437
22 C / -0.220756 / -0.48721 / 45 Ni / 0.495322 / 0.65452
23 H / 0.12082 / 0.12306 / ------

Table S5. Atomic charges for optimized geometry of [Cu(L)] complex

Atom / Mulliken atomic
charge / Natural atomic charge / Atom / Mulliken atomic
charge / Natural atomic charge
1 C / 0.130713 / 0.04058 / 24 H / 0.133732 / 0.25122
2 C / 0.192878 / 0.11391 / 25 C / -0.051534 / -0.2764
3 C / 0.209103 / 0.17844 / 26 H / 0.112413 / 0.23688
4 C / 0.52112 / 0.59622 / 27 H / 0.118393 / 0.23277
5 H / 0.094312 / 0.24721 / 28 N / -0.499562 / -0.56399
6 C / -0.084621 / -0.21137 / 29 C / 0.312023 / 0.36242
7 C / -0.098523 / -0.23825 / 30 C / -0.381962 / -0.74523
8 C / -0.086189 / -0.21516 / 31 H / 0.134194 / 0.26196
9 C / -0.102199 / -0.255 / 32 H / 0.1334 / 0.25656
10 H / 0.103538 / 0.25342 / 33 H / 0.138196 / 0.25626
11 H / 0.090589 / 0.24156 / 34 C / 0.0025 / -0.20164
12 H / 0.086954 / 0.24119 / 35 C / -0.124001 / -0.20448
13 N / -0.432761 / -0.48359 / 36 C / 0.394859 / 0.42451
14 N / -0.447883 / -0.39549 / 37 C / -0.107238 / -0.27634
15 O / -0.572868 / -0.67211 / 38 H / 0.080729 / 0.23103
16 C / 0.150786 / 0.14286 / 39 C / -0.12454 / -0.28327
17 H / 0.126843 / 0.22265 / 40 C / -0.075745 / -0.20434
18 N / -0.450906 / -0.54659 / 41 H / 0.079839 / 0.23879
19 C / -0.048348 / -0.26522 / 42 H / 0.10966 / 0.25361
20 H / 0.106542 / 0.23068 / 43 H / 0.088453 / 0.24037
21 H / 0.129347 / 0.2428 / 44 O / -0.60237 / -0.66795
22 C / -0.207009 / -0.48301 / 45 Cu / 0.606023 / 0.93553
23 H / 0.11112 / 0.25601 / ------

Table S6. Atomic charges for optimized geometry of [Zn(L)] complex

Atom / Mulliken atomic
charge / Natural atomic charge / Atom / Mulliken atomic
charge / Natural atomic charge
1 C / 0.127233 / 0.0382 / 24 H / 0.13295 / 0.24989
2 C / 0.193905 / 0.11401 / 25 C / -0.060249 / -0.27771
3 C / 0.206653 / 0.1782 / 26 H / 0.124372 / 0.24392
4 C / 0.502481 / 0.59823 / 27 H / 0.104966 / 0.23242
5 H / 0.095297 / 0.24779 / 28 N / -0.566795 / -0.63701
6 C / -0.083569 / -0.21043 / 29 C / 0.297959 / 0.36168
7 C / -0.097695 / -0.23841 / 30 C / -0.380021 / -0.74699
8 C / -0.085859 / -0.21351 / 31 H / 0.131597 / 0.26031
9 C / -0.10186 / -0.25426 / 32 H / 0.132903 / 0.25614
10 H / 0.103968 / 0.25407 / 33 H / 0.135241 / 0.25544
11 H / 0.0922 / 0.24232 / 34 C / -0.008949 / -0.21673
12 H / 0.0885 / 0.24199 / 35 C / -0.122386 / -0.20125
13 N / -0.427286 / -0.48321 / 36 C / 0.366071 / 0.42226
14 N / -0.446492 / -0.39565 / 37 C / -0.109963 / -0.28593
15 O / -0.657612 / -0.78282 / 38 H / 0.079126 / 0.22917
16 C / 0.157785 / 0.14473 / 39 C / -0.12538 / -0.29475
17 H / 0.120643 / 0.22169 / 40 C / -0.073982 / -0.20231
18 N / -0.524535 / -0.60101 / 41 H / 0.076395 / 0.23747
19 C / -0.044349 / -0.27017 / 42 H / 0.095551 / 0.24839
20 H / 0.109744 / 0.22719 / 43 H / 0.084525 / 0.23819
21 H / 0.133812 / 0.25177 / 44 O / -0.698541 / -0.80717
22 C / -0.216055 / -0.49118 / 45 Zn / 1.025245 / 1.36032
23 H / 0.112456 / 0.25472 / ------