Gas-phase reactions of Tc+, Re+, Mo+ and Cu+ with alkenes

Coordination and Solvation in Gas-Phase Ag+(C2H2)n Complexes Studied with Selected-Ion Infrared Spectroscopy

“…Cation−π interactions involving transition metals are ubiquitous throughout organometallic chemistry. − These noncovalent binding forces are important in structural biology, − and they play pivotal roles in catalytic processes. − Transition metal sites in zeolites and metal–organic frameworks (MOFs) have demonstrated enhanced reactivity and selectivity compared to traditional catalysts toward substrates with π-electron systems. − The reactivity of open metal sites in MOFs also makes them promising materials for the storage and separation of gases such as acetylene. , Accordingly, a clearer understanding of transition metal cation−π interactions is necessary to guide the rational design of new catalysts and materials. Isolated cation–molecular complexes have been studied with mass spectrometry − and computational chemistry − to gain a molecular-level understanding of these interactions. More recently, details on the structure and bonding of metal ion complexes have been revealed via spectroscopy of size-selected complexes. − In the present work, we employ similar experimental methods, complemented by density functional theory (DFT) computations, to investigate the structures, coordination, and bonding interactions of gas-phase Ag + (C 2 H 2 ) n complexes.…”

“…Moreover, when combined with computational chemistry, they form a powerful tool to investigate the structure, coordination, and bonding interactions of ion–molecular complexes. Mass spectrometry has been previously used to obtain insight into the binding energies, fragmentation channels, and reactivity of metal cation−π complexes with one or two ligands. − Theoretical studies have also provided information about the electronic structures and geometries of these species, − and electronic spectroscopy has revealed details about their preferred bonding configurations and energetics. ,− However, infrared spectroscopy on these and larger species is necessary to obtain structural information. Infrared photodissociation spectroscopy is convenient for studying multiligand complexes because the fragmentation behavior of larger molecules indicates their coordination numbers and, in some cases, identifies products from insertion reactions.…”

Cation−π and CH−π Interactions in the Coordination and Solvation of Cu+(acetylene)n Complexes

“…Vibrational spectroscopy in the gas phase, paired with computational predictions of structures and spectra, provides direct probes of structure and bonding. Information on the reactivity, binding energies, and fragmentation pathways of metal–acetylene ions has been provided previously by mass spectrometry. − Several groups have also investigated the electronic structures and geometries of these complexes with theory. − Electronic spectroscopy has been used to provide details on the bonding configurations and energetics in these systems. − However, these studies were limited to complexes with only one ligand. Infrared spectroscopy is well-suited for studying these complexes, as it can reveal the structure and coordination numbers of multiligand complexes and help to characterize the bonding interactions of inner-sphere versus solvent molecules.…”

On the Origin of Reactivity Enhancement/Suppression upon Sequential Ligation: [Re(CO)x]+/CH4 (x=0–3) Couples

“…Further, the thermal reaction of methane with [ReN] + results in the competitive generation of [HRe(NCH)] + and [NRe(CH 2 )] + . As to atomic [Re] + , while it efficiently reacts with larger hydrocarbons like C 2 H 4 , C 4 H 8 , cyclo‐C 6 H 10 , and 1,5‐cyclo‐C 8 H 12 , this metal cation is inert towards methane under thermal conditions…”