Synthesis and structural studies of novel Co(III) ternary complexes containing N(4)-substituted thiosemicarbazones of 2-hydroxyacetophenone and heterocyclic bases

Correlation between quadrupole splitting (Δ) and the θ angle (C–Sn–C) in five-coordinate diphenyltin(IV) complexes. X-ray crystal structures of [Ph2Sn(hacm)] and [Ph2Sn(hacmm)] containing O,N,S-tridentate N 4-heterocyclic thiosemicarbazones

“…The Lower quadrupole splitting values for complexes (1), (2) and (9) indicate that the charge distribution around the tin(IV) nucleus is more symmetrical and their geometry is considerably less distorted [21]. These results are supported by X-ray crystallography data which shows that these three compounds possess the equatorial angle C-Sn-C very close from the ideal value of 120°observed in trigonal bipyramidal geometry.…”

“…As a result of the deprotonation of the ligands upon complexation, the i.r. spectra of complexes lack m(O-H), m(N-H) and m(C=S) absorptions which are present in the spectra of free thiosemicarbazones [9,10]. Two new intense bands at 1561 and 1563 cm )1 found in the spectra of the complexes [Ph 2 Sn(hacmm)] and [Ph 2 Sn(hacmm)], respectively, are assigned to m(C=N), this is because while coordinating to the Sn(IV) ion, the ligands molecule undergo deprotonation, generating a double bond between N2 and C9 atoms and coordination via thiolate rather than a thione [9].…”

“…N 4 -heterocyclic thiosemicarbazones forms an important class of compounds possessing biological activity [4][5][6]. Their biological activity is due to ability to form chelates with vital ions bonding through a sulfur and two nitrogen, N,N,S-donor [7,8] or oxygen, nitrogen and sulfur atoms, O,N,S-donor [9,10]. Since tin(IV) complexes have also significant pharmacological activity and little research has been done on its N 4 -heterocyclic thiosemicarbazones derivatives, we report herein studies involving N 4 -heterocyclic thiosemicarbazones and their complexes [Ph 2 (hacm)] and [Ph 2 Sn(hacmm)].…”

Synthesis, characterization, crystal structure and electrochemical behavior of a nickel(II) complex of 5,6-dihydro-2H-pyran-3-aldehyde thiosemicarbazone

“…Moreover, N-heterocyclic thiosemicarbazones have attracted the greatest attention in recent years, and many reports involve crystal structures of these thiosemicarbazones and/or their metal complexes [14][15][16][17][18][19][20][21][22][23][24]. However, less attention has been given to O-heterocyclic thiosemicarbazones [25][26][27].…”

[(Tmp)Co2L] Complexes through Preassembly on 2,6‐Diformyl‐ and 2,6‐Bis(benzylimino)‐4‐methylphenolate Templates

“…In MeCN solution, the brown compound 1 shows a band at 639 nm (ε = 470 L mol -1 cm -1 ) and is characteristic of the octahedral cobalt(III) environment ( [28] So for compounds 2 and 3 the bands at 562 and 591 nm may be assigned to the spin-allowed transitions from 4 T 1g (F) to 4 A 2g .…”