Evidence for Electron Transfer in the Reactions of Hydrated Monovalent First-Row Transition-Metal Ions M(H₂O)_n⁺, M = V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, n < 40, toward 1-Iodopropane

Abstract

Hydrated metal ions in the gas phase serve as model systems to investigate the impact of hydration on the chemistry of monovalent transition-metal centers. As a prototypical organometallic reaction involving electron transfer, the reactions of M(HO), M = V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, n < 40, with CHI are studied by Fourier transform ion cyclotron resonance mass spectrometry. While no reaction was observed for vanadium, three different reactions were observed with the other metals, two of them involving the oxidation of the metal ion. Ligand exchange occurs for all metals except zinc. This reaction is sensitive to the size of the solvation shell and is observed predominantly for small cluster sizes. For Cr, Co, and Zn, the metal center is oxidized with formation of MI ions. The formation of [MCH(CHI)], M = Co, Ni, proceeds most likely via oxidative addition of CHI to the metal ion via insertion into the C-I bond, followed by reductive elimination of HI. For Cu, this reaction seems to stop after the insertion of the metal into the C-I bond, resulting in Cu(CHI)(HO). The reactions are compared with earlier studies on electron transfer involving hydrated metal centers.

Microsolvation of Zn cations: infrared multiple photon dissociation spectroscopy of Zn+(H2O)n (n = 2–35)

“…47 With 1-iodopropane, Zn + (H 2 O) n reacts efficiently to ZnI + (H 2 O) m , again with oxidation of the Zn centre. 48 These studies showed that hydrated monovalent zinc ions can be oxidized by suitable reactants, but the details of the reactions and their cluster size-dependence can be quite complex. The question arises whether hydrated electrons are formed in sufficiently large clusters, similar to Mg + (H 2 O) n , 21 however an insertion to form HZnOH + does not seem plausible, given the lack of H/D exchange in the D 2 O experiment.…”

Photochemistry and spectroscopy of small hydrated magnesium clusters Mg+(H2O)n, n = 1–5

“…32 They also explained the switch off for the hydrogen loss process for larger clusters due to the barrier increase when the solvated electron moves beyond the third solvation shell. 15 Our group has a long history in studying the reactivity of hydrated metal ions, 13,16,[33][34][35][36][37][38][39][40][41][42][43][44][45][46][47] using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) which is well suited for this task as it allows highest mass resolution coupled with long storage times to allow multiple collisions with reactant gases. In the present study, we couple the mass spectrometer with a tunable optical parametric oscillator (OPO)/amplifier system to conduct photodissociation experiments.…”

Vanadium Cluster Neutrals Reacting with Water: Superatomic Features and Hydrogen Evolution in a Fishing Mode

“…Metal cluster stability and reactivity are often determined by gas-phase reactions. , For example, the reactivity of Al cluster anions with water demonstrated that complementary active sites account for the size-selective reactivity, unveiling dependence on geometric rather than electronic shell structure . Also, extensive studies have revealed the diverse reactivities of transition metal ions and clusters in a variety of conditions, − motivated by the application potentials in catalysis, battery cathodes, and magnetic materials. , Among them, the studies on the size-dependent reactivity of vanadium clusters with CO, NO, O 2 , D 2 , N 2 , C x H x , alcohols, and many other species have been conducted, − , allowing us to quantitatively estimate the reaction probability and catalytic behavior. In particular, several studies have revealed the geometric structures, electronic properties, and kinetics involved in the novel coordination chemistry of vanadium cations with water, − as well as electronic properties of hydrated V n clusters .…”

“…Also, extensive studies have revealed the diverse reactivities of transition metal ions and clusters in a variety of conditions, − motivated by the application potentials in catalysis, battery cathodes, and magnetic materials. , Among them, the studies on the size-dependent reactivity of vanadium clusters with CO, NO, O 2 , D 2 , N 2 , C x H x , alcohols, and many other species have been conducted, − , allowing us to quantitatively estimate the reaction probability and catalytic behavior. In particular, several studies have revealed the geometric structures, electronic properties, and kinetics involved in the novel coordination chemistry of vanadium cations with water, − as well as electronic properties of hydrated V n clusters . Recently, we studied the reactions of ionic vanadium clusters and found significant H 2 release from single H 2 O molecules in reacting with cationic V n + , revealing decisive advantages of vanadium clusters (rather than single atoms) for hydrogen evolution reaction (HER) from water.…”