1340586-41-5Relevant academic research and scientific papers
Coordination and conformational isomers in mononuclear iron complexes with pertinence to the [FeFe] hydrogenase active site
Orthaber, Andreas,Karnahl, Michael,Tschierlei, Stefanie,Streich, Daniel,Stein, Matthias,Ott, Sascha
, p. 4537 - 4549 (2014/03/21)
A series of six mononuclear iron complexes of the type [Fe(X-bdt)(P R2NPh2)(CO)] (PR 2NPh2 = 1,5-diaza-3,7-diphosphaoctane, bdt = benzenedithiolate with X = H, Cl2 or Me and R = Ph, Bn, Cyc or tert-Bu) was prepared. This new class of penta-coordinate iron complexes contains a free coordination site and a pendant base as essential structural features of the [FeFe]-hydrogenase active site. The bidentate nature of the PR2NPh2 ligands was found to be crucial for the preferential formation of coordinatively unsaturated penta-coordinate complexes, which is supported by first principle calculations. IR-spectroscopic data suggest the presence of coordination isomers around the metal center, as well as multiple possible conformers of the PR 2NPh2 ligand. This finding is further corroborated by X-ray crystallographic and computational studies. 31P{1H}-NMR- and IR-spectroscopic as well as electrochemical measurements show that the electronic properties of the complexes are strongly, and independently, influenced by the P-substituents at the PR2NPh2 ligand as well as by modifications of the bdt bridge. These results illustrate the advantages of this modular platform, which allows independent and selective tuning through site specific modifications. Potential catalytic intermediates, namely singly reduced and protonated complexes, have been further investigated by spectroscopic methods and exhibit remarkable stability. Finally, their general capacity for electro-catalytic reduction of protons to molecular hydrogen was verified.
Versatile synthesis of PR2NR′ 2 ligands for molecular electrocatalysts with pendant bases in the second coordination sphere
Doud, Michael D.,Grice, Kyle A.,Lilio, Alyssia M.,Seu, Candace S.,Kubiak, Clifford P.
scheme or table, p. 779 - 782 (2012/05/04)
Two 1,5-diaza-3,7-diphosphacyclooctane (P2N2) ligands with alkyl-substituted phosphines have been synthesized via a versatile method that allows for improved control of the phosphine substituent. The methyl- and benzyl-substituted phosphine P2N2 ligands (P Me2NPh2 and PBn 2NPh2) were synthesized and characterized by 31P{1H} NMR, 1H NMR, and elemental analysis, and their corresponding [Ni(PR2NPh 2)2](BF4)2 complexes were synthesized and characterized by 31P{1H} NMR, 1H NMR, and electrochemistry. The structure of the complex [Ni(P Me2NPh2)2](CF 3SO3)2 was characterized by X-ray crystallography.
Studies of a series of [Ni(PR2NPh 2)2(CH3CN)]2+ complexes as electrocatalysts for H2 production: Substituent variation at the phosphorus atom of the P2N
Kilgore, Uriah J.,Stewart, Michael P.,Helm, Monte L.,Dougherty, William G.,Kassel, W. Scott,Dubois, Mary Rakowski,Dubois, Daniel L.,Bullock, R. Morris
experimental part, p. 10908 - 10918 (2011/12/13)
A series of [Ni(PR2NPh2) 2(CH3CN)](BF4)2 complexes containing the cyclic diphosphine ligands [PR2NPh 2 = 1,5-diaza-3,7-diph
Kilgore, Uriah J.,Stewart, Michael P.,Helm, Monte L.,Dougherty, William G.,Kassel, W. Scott,Dubois, Mary Rakowski,Dubois, Daniel L.,Bullock, R. Morris
experimental part, p. 10908 - 10918 (2011/12/13)
A series of [Ni(PR2NPh2) 2(CH3CN)](BF4)2 complexes containing the cyclic diphosphine ligands [PR2NPh 2 = 1,5-diaza-3,7-diph
