Metal complexes of sulfur–nitrogen chelating agents. V. 2-N-Ethylaminocyclopentene-1-dithiocarboxylic acid complexes of Ni(II), Pd(II), Pt(II), Co(II), Co(III), and Cu(I)

Abstract

2-N-Ethylaminocyclopentene-1-dithiocarboxylic acid (EACDA) acts as an ambidentate ligand toward several metal ions. Bis-chelates have been obtained with Ni(II), Pd(II), Pt(II), and Co(II), and tris-chelate with Co(III). Cu(I) forms a 1:1 complex. The bonding sites involved in the metal chelates and their stereochemistry have been ascertained from electronic, infrared and nmr spectra, magnetic moment, and thermal analysis. In the Co(II) and Co(III) chelates bonding takes place from (S,S−) donor sites, whereas in the Ni(II), Pd(II), and Pt(II) chelates (N,S−) type bonding occurs. The Cu(I) complex appears to be polymeric in nature.

Electronic Structures and Reduction Potentials of Cu(II) Complexes of [N,N′-Alkyl-bis(ethyl-2-amino-1-cyclopentenecarbothioate)] (Alkyl=Ethyl, Propyl, and Butyl)

“…The n a (C-S) band splitting and the blue shift of the n s (CS-S) band in the CSS-R moiety, compared with the free ligand, indicate a monodentate dithio group, similar to dithiocarbamate complexes reported by Nag [4]. Assuming C 2v core coordination, the three Cu(II)N 2 bands are: B 2 ,n a (M(II)N) stretching near 520 cm -1 ; A 1 , n a (Cu(II)N) stretching near 490 cm -1 , similar to values reported for Cu(II)N [4,5]; and A 1 , d(Cu(II)N) bending, appearing in the far infrared, along with three Cu(II)S 2 bands [12].…”

“…In this tribute to him, we report an extension of research on certain Cu(II)N 2 S 2 complexes [4][5][6][7] to include those with N,N¢-alkyl-bis(ethyl-2-amino-1-cyclopentenecarbodithioate) [alkyl=ethyl (L2), propyl (L3), and butyl (L4)] ligands. We believe that Cu(II) complexes in the series L2-L4 would have been of interest to Jørgensen, as their d-d spectra and reduction potentials can be interpreted readily in terms of systematic variations in coordination geometry.…”

Design and Synthesis of Metal Complexes of (2E)‐2‐[(2E)‐3‐Phenylprop‐2‐en‐1‐ylidene]hydrazinecarbothioamide and Their Photocatalytic Degradation of Methylene Blue

“…The absence of (N–H) band in the spectrum of complex provides a strong evidence for the ligand coordination around metal ion in its deprotonated form in nickel complex (except for copper and cobalt complexes). The absorption attributed to (C=S) at 1178 cm −1 in the spectra of the free ligand shifts to 1159 cm −1 in the spectra of the copper complex, indicating coordination through a thioketonic sulphur, whereas in Ni(II) complex the disappearance of (C=S) and the presence of new band at 677 cm −1 indicate the coordination of thiolate sulphur [ 26 ] and also the presence of (M–S) band at 472 cm −1 [ 27 , 28 ].…”

Synthesis and spectroscopic studies of the cobalt(II) complex with methyl 2-pyridylmethylidenehydrazinecarbodithioate (HNNS)

“…Moreover, the IR spectra of the present cobalt(II) complex does not contain the m(NH) band of the free ligands supporting that they deprotonate during coordination with the cobalt(II) ion. Additional evidence for coordination of the imine nitrogen is the presence of m(Co-N) (442 cm )1 ) band in the 435-450 cm )1 range for the divalent metal centers [19]. Assignment of other characteristic bands of the ligands and its cobalt(II) complex are given in Table 3.…”