15040-15-0Relevant academic research and scientific papers
Structural and spectroscopic characterization of five coordinate iron and cobalt bis(dithiolene)-trimethylphosphine complexes
Selby-Karney, Troy,Grossie, David A.,Arumugam, Kuppuswamy,Wright, Eyglo,Chandrasekaran
, p. 477 - 483 (2017)
Heteroleptic bis(dithiolene)-phosphine iron and cobalt complexes [Fe(adt)2(PMe3)] (1) and [Co(adt)2(PMe3)] (2) (adt?=?para-anisyldithiolene) have been synthesized from corresponding bis(dithiolene) dimers [M2(adt)4]2 (M?=?Fe, Co) by reacting with excess PMe3 in dichloromethane. Solid-state structures of 1 and 2 have been determined by single crystal X-ray crystallography, and the dithiolene ligands C[sbnd]S (≈1.72??) and C[sbnd]C (≈1.37??) bond distances reveal the coordination of π-radical monoanionic dithiolene (adt?1?) ligands to metal centers. Intense low energy ligand-to-ligand-charge transfer (LLCT) absorption band (743?nm for 1; 905?nm for 2) in UV–vis spectra and characteristic ν(C[dbnd]S?) (1168?cm?1 for 1; 1170?cm?1 for 2) in IR spectra affirms coordination of π-radical monoanionic dithiolenes to divalent metal ions. The cyclic voltammogram of 1 and 2 shows reversible oxidation and reduction waves attributed to MII?→?MIII?+?e? (+0.52?V for 1;?+0.29?V for 2) and adt?1??+?e??→?adt2? (?0.63?V for 1;??0.46?V for 2) redox process respectively. Comprehensive structural and spectroscopic investigations conclude, [M2III(adt2?)2(adt?1-)2]?→?2 [MII(adt?1-)2(PMe3)] intramolecular redox interplay during phosphine coordination induced cleavage of homoleptic bis(dithiolene) dimers to produce square pyramidal complexes.
