Zinc(II) and copper(II) complexes with benzothiadiazole Schiff-base ligands

Six-coordinated nickel(ii) complexes with benzothiadiazole Schiff-base ligands: synthesis, crystal structure, magnetic and HFEPR study

“…S1†). 30,31 The cis -angles cover the range 79.42(6)–97.88(6)° for 1 and 80.19(16)–98.18(17)° for 2 , whereas the trans ones go from 167.90° to 170.94° and 168.05° to 176.32° for 1 and 2 , respectively. The bond valence sum (BVS) analysis 35,36 applied to the corresponding bond lengths indicates the +2 oxidation state for the nickel ions (Table 2).…”

“…The Schiff base ligands were obtained according to our previously described procedures. 30,31 Note that the procedure for both complexes 1 and 2 is similar with the one previously described for the cobalt(II) complex [CoL 2 2 ]•CH 2 Cl 2 . 31…”

“…[26][27][28][29] On the other hand, our recently reported Schiff base ligands based on BTD, as products of condensation of 4-amino-2.1.3benzothiadiazole and salicylaldehyde (HL 1 ) or ortho-vanillin (HL 2 ) (Chart 1) provided several metal complexes. For example, the copper complexes [CuL 1 (hfac)] and Cu(L 2 ) 2 30 show very weak intermolecular antiferromagnetic interactions in the low temperature region and the neutral [CoL with L 2 exhibit slow relaxation of the magnetization under dc applied magnetic field, characteristic of single-ion magnet (SIM) behaviour. However, to the best of our knowledge, the magnetic properties of nickel(II) complexes with BTD ligands have not been investigated to date.…”

Fluorescence vs. Phosphorescence: Which Scenario Is Preferable in Au(I) Complexes with Benzothiadiazoles?

“…According to TD-DFT calculations for the single molecules at their ground-state optimised geometry ( Tables S1–S6 ), the long wavelength band corresponds to the S 0 – S 1 transition between HOMO and LUMO orbitals ( Figure 4 , Figures S4 and S5 ). The transition has a locally excited (LE) character with a notable contribution of an intraligand charge transfer (ILCT) from the periphery to the thiadiazole moiety, which is common for btd derivatives ( Figure 4 ) [ 28 , 29 , 30 , 31 ]. In addition, compound 1 features a minor contribution of Au and Cl orbitals to the HOMO, which implies the presence of (M+X)LCT (metal- and halogen-to-ligand charge transfer).…”

Benzothiadiazolyl‐pyridine and ‐2,2′‐bipyridine Ligands for Luminescent and Magnetic Complexes

“…As such, Pd(II) cyclopalladated complexes of 4‐aryl‐BTD, [23] a Zn(II) MOF derived from BTD‐4,7‐dicarboxylic acid, [24] or NIR‐emissive tetranuclear Er(III) complexes with 4‐hydroxo‐2,1,3‐benzothiadiazolate, [25] all containing bidentate ligands with the participation of at least one of the nitrogen atoms of the thiadiazole ring, have been described. More recently, we have reported monotopic tridentate Schiff‐base BTD ligands resulting from the condensation of 4‐amino‐BTD with salicylaldehyde and ortho ‐vanillin, together with their Zn(II), [26] Cu(II) [26] and Co(II) complexes, [27] the latter showing field‐induced single‐ion magnet (SIM) behaviour. A particularly appealing combination is that of BTD with 2‐pyridyl units in the 4,7‐positions of BTD, providing the bidentate ditopic ligand 4,7‐di(2′‐pyridyl)‐2,1,3‐benzothiadiazole [(2′‐Py) 2 BTD in Scheme 1] which is able in principle to afford mononuclear and binuclear metal complexes.…”