Related Experiment Video
Updated: Jun 21, 2026

Catalytic Reactions at Amine-Stabilized and Ligand-Free Platinum Nanoparticles Supported on Titania During Hydrogenation of Alkenes and Aldehydes
Published on: June 24, 2022
Diiron proton reduction catalysts possessing electron-rich and electron-poor naphthalene-1,8-dithiolate ligands
Robert J Wright1, Christopher Lim1, T Don Tilley1
1Department of Chemistry, University of California, Berkeley, CA 94720 (USA), Fax: (+1) 510-642-8940.
Abstract:
The diiron complexes [Fe(2)(CO)(6)(1,8-S(2)-2,4,5,7-Cl(4)C(10)H(2))] (3), [Fe(2)(CO)(6)(1,8-S(2)C(10)H(6))] (4), and [Fe(2)(CO)(6)(1,8-S(2)-2,7-tBu(2)C(10)H(4))] (5) were synthesized in moderate yield from naphthalene-1,8-dithiols and [Fe(3)(CO)(12)]. They were characterized by IR, (1)H and (13)C NMR spectroscopy and 3 and 4 were characterized by X-ray crystallography. They contain a butterfly Fe(2)S(2) core with Fe-Fe distances of 2.529(1) (3) and 2.506(1) A (4). Cyclic voltammetry (CH(2)Cl(2)/nBu(4)PF(6)) revealed two one-electron reductions, at potentials more positive than those for the related [Fe(2)(CO)(6)(S(CH(2))(3)S)] (1), and one one-electron oxidation. The first reduction of the electron poor 3 (-1.60 V vs Fc/Fc(+)) is 240 mV more positive than the first reduction of the electron rich 5 (-1.84 V). Electrochemical studies revealed that 3-5 facilitate the proton reduction of p-toluenesulfonic acid. The rates of catalysis, with a 95% confidence limit, are 2.4+/-0.8 (1), 5.2+/-0.8 (3), 3.1+/-1.1 (4), 2.9+/-0.6 (5), and 4.5+/-0.2 h(-1) for the related [Fe(2)(CO)(6)(1,2-S(2)C(6)H(4))]. The rates were determined by bulk electrolysis at -1.70 V (Fc/Fc(+)), which correspond to an overpotential of 1.05 V for p-toluenesulfonic acid.
More Related Videos
Related Concept Videos
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Diels–Alder Reaction: Characteristics of Dienophiles
Characteristics of Dienophiles
Generally, the best dienophiles are alkenes containing electron-withdrawing substituents such as carbonyl, nitrile, and nitro groups. The feasibility of a Diels–Alder reaction depends on...
EDTA: Chemistry and Properties
Diels–Alder Reaction: Characteristics of Dienes
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is more stable, the...
Complexometric Titration: Ligands

