Table 1: The analytical data of the proposed stoichiometry of the complexes.

No Mol. formula/general formula Color M.P. Mol. Wt. C% calcd. (found) H% calcd. (found) N% calcd. (found)
1 Mn(C8H9N2O)2 Pale yellow 220 352.94 54.40 5.10 15.86
Mn(L)2 (54.60) (5.82) (15.81)
2 Cr(C8H9N2O)3 Greenish yellow 205 498.996 57.71 5.41 16.83
Cr(L)3 (57.06) (6.00) (16.77)
3 Fe(C8H9N2O)3 Brownish yellow 108 502.84 57.27 5.37 16.70
Fe(L)3 (57.27) (5.25) (16.62)
4 Co(C8H9N2O)2 Yellow 210 356.93 53.79 5.04 15.69
Co(L)2 (53.50) (5.15) (15.80)
5 Ni(C8H9N2O)2·2H2O Greenish yellow 207 392.69 48.89 5.60 14.26
Ni(L)2.2H2O (48.70) (5.61) (14.50)
6 Cu(C8H9N2O)2·2H2O Gray yellow 220 397.55 48.29 5.53 14.08
Cu(L)2.2H2O (48.70) (5.93) (14.79)
9 Cd(C8H9N2O)2 Pale yellow >300 410.41 46.78 4.39 13.64
Cd(L)2 46.60 4.41 13.55
10 Zn(C8H9N2O)2 Yellow 205 363.39 52.84 4.95 15.41
Zn(L)2 (52.80) (5.00) (15.19)
11 Hg(C8H9N2O)2 Yellow 198 498.5 38.51 3.61 11.23
Hg(L)2 (38.98) (3.55) (11.34)
12 Ce(C8H9N2O)3 Yellow 218–221 587.12 49.05 4.60 14.26
Ce(L)3 (50.76) (4.59) (14.04)
13 UO2(C8H9N2O)2H2O Yellow 230 586.0 38.22 3.41 9.55
UO2(L)2.H2O (38.54) (3.64) (9.60)