Pendant bases as proton transfer relays in diiron dithiolate complexes inspired by [Fe–Fe] hydrogenase active site

Diiron propanedithiolate complex bearing the pyridyl-functionalized phosphine ligand axially coordinated to a photosensitizer zinc tetraphenylporphyrin

“…A diiron propanedithiolate unit has two fused six-membered rings, in which one six-membered ring C8C7S1Fe2S2C9 has a boat conformation and another sixmembered ring C8C7S1Fe1S2C9 adopted a chair conformation. The pyridyl-functionalized phosphine ligand PyNHPPh 2 resides in an axial position of the square-pyramidal geometry of the Fe2 atom which is consistent with previously reported corresponding diiron dithiolate complexes with monophosphine ligands such as (m-PDT) Fe 2 (CO) 5 (Ph 2 PCH 2 COOH) [20], (m-PDT)Fe 2 (CO) 5 [Ph 2 PNHCH 2 CH 2 N(CH 3 ) 2 ] [21], and [(m-SCH 2 )CH(OH)]Fe 2 (CO) 5 (PPh 3 ) [22]. The Fe1-Fe2 bond length [2.5054(14) Å] is close to its parent complex (m-PDT)Fe 2 (CO) 6 [21], but shorter than those in the structures of natural enzymes Clostridium pasteurianum and Desulfovibrio desulfuricans (2.55e2.62 Å) [23,24].…”

Synthesis and structural characterization of iron–sulfur complexes with hydrophilic nitrogen–phosphorus ligands

“…4, complex 1 is composed of a typical butterfly [Fe 2 S 2 ] cluster ligated by a dithiolate ligand bridging the di-iron core, together with five carbonyls and one monophosphine ligand. The P(1) atom of the Ph 2 P(NHC 6 H 4 Cl) ligand resides in the apical site in the square pyramidal coordination geometry of the Fe(2) core, which is consistent with those reported in other phosphinemonosubstituted di-iron dithiolate complexes [30][31][32][33][34][35][36].…”

Preparation, structures and electrochemical property of diiron dithiolate complexes with hydrophilic N-donor ligands

“…1, in the molecular structure of 2, there exists an intramolecular hydrogen bond between the amino proton and the bridging sulfur atom, with the H/S distance and NÀH/S angle being 2.598 Å and 132.94 , respectively. The N/S distance of the hydrogen bond in 2 is 3.245 Å, which is slightly shorter than that reported for [Fe 2 (mpdt)(CO) 5 (PPh 2 NH(2-NH 2 C 6 H 4 )] (3.460 Å) [32]. In the crystal structures of 3 and 4, there exists an intermolecular hydrogen bond between the amino group of one molecule and the bridging sulfur atom of another molecule, giving rise to a dimer (Fig.…”