Synthesis, Spectroscopic, and Thermal Investigations of Metal Complexes with Mefenamic Acid

Table 3

Thermal decomposition data of complexes in air.

Compounds	Ranges of decomp., °C	DTA peaks, °C	Mass loss, %		Intermediate and final solid products
			Found	Calc.
Mn(mef)2·3H2O	60–240	120 endo	9.0	9.17	Mn(mef)2
	240–740	320,600 exo	78.0	77.68	Mn2O3
	740–900	860 exo	1.0	1.80	Mn3O4
Co(mef)2·2H2O	60–110	100 endo	3.0	3.13	Co(mef)2·H2O
	130–240	-	3.0	3.13	Co(mef)2
	250–520	340 endo; 470 exo	73.0	73.07	CoCO3
	530–660	570 exo	7.0	6.72	Co3O4
	>900	920 exo	1.0	0.93	CoO
Ni(mef)2·2H2O	50–180	80 endo	6.5	6.30	Ni(mef)2
	190–460	340, 430 exo	73.0	73.10	NiCO3
	460–550	490 exo	8.5	9.0	NiO+Ni
	550–750	570 exo	1.5	1.39	NiO
Cu(mef)2·2H2O	100–180	150 endo	6.5	6.66	Cu(mef)2
	190–840	550, 640 exo	80.0	80.08	CuO
Zn(mef)2·2H2O	100–160	130 endo	3.0	3.10	Zn(mef)2·H2O
	160–190	180 endo	3.0	3.10	Zn(mef)2
	200–490	420 exo	72,0	72.26	ZnCO3
	490–640	510 endo, 580 exo	8.0	7.56	ZnO
Cd(mef)2·2H2O	110–160	150 endo	6.0	5.73	Cd(mef)2
	210–380	300 endo,; 340 exo	67.0	66.86	CdCO3
	470–760	550 exo	7.0	6.59	CdO

Mass increase on TG curve.