Trigonal‐Bipyramidal vs. Octahedral Coordination in Indium(III) Complexes with Potentially S,N,S‐Tridentate Thiosemicarbazones

Abstract

Three bis‐chelates of indium(III) with (partially fluorinated) S,N,S‐tridentate thiosemicarbazones (H2L) were prepared and their structures were studied in solution and in the solid state by NMR, ESI MS and single‐crystal X‐ray diffraction. The three compounds are isostructural in solution with five‐coordinate InIII ions and two differently coordinated thiosemicarbazonato ligands, [In(L)(HL)]. A temperature‐dependent 1H NMR study reflects the presence of dynamic processes in the molecules such as the resolution of hindered rotation around CN bonds with partial double‐bond character and the pH‐triggered isomerization between 5‐ and 6‐coordinate species. The latter is confirmed by the isolation of compounds with different solid‐state structures, [In(L)(HL)] and [In(L)2]–, depending on fluorine‐substitutions in the periphery of the thiosemicarbazones.

Synthesis and theoretical study of a mixed-ligand indium(iii) complex for fabrication of β-In2S3 thin films via chemical vapor deposition

“…The molecular structure of [2] showed a trigonal-bipyramidal coordination sphere for the indium ion, where the trigonal basal plane is formed by two sulfur atoms of the dianionic thiolate ligand, and the oxygen atom of the N,O-ß-heteroarylalkenolate ligand while the apical positions are occupied by the nitrogen atom present in the bridging amine group of the dianionic thiolate ligand and one nitrogen atoms of the heteroarylalkenolate ligand. The In-S bond distances (TableS1) in [1] were found to be in the range of 2.404(1)-2.676(2) Å, while the bond lengths of the bridging sulfur atoms in In1-S2 and In1_a-S2 were found to be longer at 2.485(1) Å and 2.676(2) Å respectively than the terminal In1-S1 bond length at 2.404(1) Å.These values correspond well with similar reported values of dimeric, trimeric and oligomeric organoindium compounds [33][34][35][36][37]. The In-N bond length (2.393(5) Å) and In-Cl bond length (2.415(1) Å) in [1] are both within the reported ranges 35,[38][39][40][41].…”

“…These values correspond well to similar reported values of dimeric, trimeric and oligomeric organoindium compounds. [33][34][35][36][37] The In-N bond length (2.393(5) Å) and In-Cl bond length (2.415(1) Å) in [1] are both within the reported ranges. 35,[38][39][40][41] Notably, the three dependent indium sub-units in [1] and their corresponding atoms display uniform bond lengths and angles.…”

Triaryltechnetium(III) and Related Complexes

“…We anticipated that with the introduction of appropriate residues such solubility limitations could be overcome; thus, at least an indirect support for the monomeric structure of [Tc­(Ph) 3 (PPh 3 ) 2 ] could be provided. In particular, fluorine or CF 3 substitutions in the periphery of ligands were recently valuable tools to increase the solubility of sparingly soluble transition metal complexes also including technetium compounds. − Indeed, the reaction of [TcCl 3 (PPh 3 ) 2 (CH 3 CN)] with 3,5-bis­(trifluoromethyl)­phenylmagnesium bromide gave the soluble aryl complex [Tc­{Ph­(CF 3 ) 2 } 3 (PPh 3 ) 2 )] ( 2 ) (Scheme ).…”

Phenylimido complexes of rhenium: fluorine substituents provide protection, reactivity, and solubility

“…Some recent work in our group with nuclear medically relevant metals such as indium, technetium or rhenium demonstrated that the structure and reactivity of metal complexes can markedly be influenced by ( partial) fluorination of the ligands. 2,[9][10][11][12] The observed changes in properties were found to be dependent on both the number of fluorine atoms and their exact position. The addition of sometimes even a single fluorine atom on a ligand also led to new reactivity patterns for both rhenium and technetium complexes.…”