Synthesis Characterization and Biological Activity Study of New Schiff and Mannich Bases and Some Metal Complexes Derived from Isatin and Dithiooxamide

Table 2

Important I.R. vibrations (cm⁻¹) for the two Mannich and Schiff base ligands and their metal complexes.

Symbol	ν NH2		ν C=O	ν C=N	Thioamide group				ν M-N	ν M-O	ν M-S	ν M-Cl
					Band (I) δ N-H + ν C-S	Band (II) ν C-N +ν C-S	Band (III) ν C-S	Band (IV) ν C=S
LIH	3138	—	1730–1735	1614	1540	1429	1195	835	—	—	—	—
	3203
C1; Mn(II)	3124	—	1732	1600	1510	1434	1190	820	248	283	325	246^a
	3371
C2; Co(II)	3072	—	1724	1602	1530	1433	1163	777	230	460	330	—
	3263									270
C3; Ni(II)	3133	—	1720	1595	1535	1427	1150	827	293	464	330	—
	3213
C4; Cu(II)	—	3315	1735	1600	1535	1434	1190	792	250	457	350	222^b
				1650					302
C5; Pd(II)	—	3392	1708	1604	1537	1430	1190	815	240	459	323	—
				1660					301
C6; Ir(III)	—	3342	1735	1614	1539	1400	1151	810	350	—	330	253^a
				1650
C7; Pt(IV)	—	3168	1700	1600	1517	1446	1114	833	254	462	329	297^a
				1650
LIIH	3043	—	1730	1614	1540	1434	1195	833	—	—	—	—
	3193
C8; Co(II)	3151	—	1700	1602	1585	1440	1130	800	393	400	327	—
	3321									227
C9; Ni(II)	3128	3249	1695	1600	1583	1484	1150	809	246	478	320	—
	3249								250	340
C10; Pd(II)	—	3425	1735	1619	1587	1450	1155	820	464	—	323	240^b
		3249		1647								210
C11; Pt(IV)	—	3230	1730	1616	1530	1430	1150	802	468	450	325	291^a
				1650						480		262
C12; Cd(II)	—	3300	1735	1616	1488	1430	1161	800	288	468	325	—
				1650						450

^a: terminal; ^b: bridging.