Hypovalent radicals. 4. Gas-phase studies of the ion-molecule reactions of cyclopentadienylidene anion radical in a flowing afterglow

1980 ◽  
Vol 102 (21) ◽  
pp. 6491-6498 ◽  
Author(s):  
Richard N. McDonald ◽  
A. Kasem Chowdhury ◽  
D. W. Setser
Keyword(s):  
Gas Phase ◽  
Anion Radical ◽  
Flowing Afterglow ◽  
Ion Molecule Reactions

Gas-phase ion-molecule reactions of dioxygen anion radical (O2-.bul.)

1985 ◽  
Vol 107 (14) ◽  
pp. 4123-4128 ◽  
Author(s):  
Richard N. McDonald ◽  
A. Kasem Chowdhury
Keyword(s):  
Gas Phase ◽  
Anion Radical ◽  
Ion Molecule Reactions ◽  
Gas Phase Ion

Unimolecular Rearrangements and Fragmentations in the Gas Phase: [1,3] Sigmatropic Isomerizations and [2 + 2] Cycloreversions

2003 ◽  
Vol 56 (5) ◽  
pp. 453 ◽  
Author(s):  
Mohammad R. Ahmad ◽  
Steven R. Kass
Keyword(s):  
Gas Phase ◽  
Wide Temperature Range ◽  
Variable Temperature ◽  
Collision Induced Dissociation ◽  
Triple Quadrupole ◽  
Flowing Afterglow ◽  
Temperature Range ◽  
Sigmatropic Rearrangements ◽  
Ion Molecule Reactions ◽  
Trimethylsilyl Ethers

Trimethylsilyl ethers of 3-buten-2-ol, 1-vinylcyclopropanol, 1-vinylcyclobutanol, and cyclobutanol were treated with fluoride over a wide temperature range (–40 to 300°C) in a variable-temperature flowing afterglow–triple quadrupole device. The structures of the resulting alkoxides and enolates were probed by ion–molecule reactions and their collision-induced dissociation (CID) spectra. Activation energies were obtained for several anion-accelerated [1,3] sigmatropic rearrangements and [2 + 2] cycloreversions. The mechanisms for these isomerizations and fragmentations (stepwise versus concerted) and their synthetic potential are discussed.

Some ion-molecule reactions of hydrogen cyanide

1978 ◽  
Vol 31 (5) ◽  
pp. 963 ◽  
Author(s):  
CG Freeman ◽  
PW Harland ◽  
JP Liddy ◽  
MJ McEwan
Keyword(s):  
Gas Phase ◽  
Hydrogen Cyanide ◽  
Rate Coefficient ◽  
Rate Coefficients ◽  
Flowing Afterglow ◽  
Ion Molecule Reactions ◽  
Positive Ions

Rate coefficients for the reactions of several positive ions with HCN in the gas phase have been measured by the flowing afterglow technique. The reactions are all of the form ������������������������ X++HCN → products . where X+ and the corresponding rate coefficient, in units of cm3 molecule-1 s-1, are: X+ = HCN+ (k 9.8×10-10); C2N+ (k 3.1×10-10); CN+ (k 2.8×10-9 CH+ (k 3.2×10-9); H3O+ (k 4.5×10-9 and HCO+ (k 3.9×10-9).

Reactivity Trends in the Gas Phase Addition of Acetylene to N-protonated Aryl Radical Cations

2020 ◽  
Author(s):  
Oisin Shiels ◽  
P. D. Kelly ◽  
Cameron C. Bright ◽  
Berwyck L. J. Poad ◽  
Stephen Blanksby ◽  
...  
Keyword(s):  
Gas Phase ◽  
Ion Trap ◽  
Radical Cations ◽  
Rate Coefficients ◽  
Similar Process ◽  
Ion Molecule Reactions ◽  
Aromatic Radicals ◽  
Polycyclic Aromatic ◽  
Gas Phase Ion ◽  
Type Radical

<div> <div> <div> <p>A key step in gas-phase polycyclic aromatic hydrocarbon (PAH) formation involves the addition of acetylene (or other alkyne) to σ-type aromatic radicals, with successive additions yielding more complex PAHs. A similar process can happen for N- containing aromatics. In cold diffuse environments, such as the interstellar medium, rates of radical addition may be enhanced when the σ-type radical is charged. This paper investigates the gas-phase ion-molecule reactions of acetylene with nine aromatic distonic σ-type radical cations derived from pyridinium (Pyr), anilinium (Anl) and benzonitrilium (Bzn) ions. Three isomers are studied in each case (radical sites at the ortho, meta and para positions). Using a room temperature ion trap, second-order rate coefficients, product branching ratios and reaction efficiencies are reported. </p> </div> </div> </div>

Sign in / Sign up

Export Citation Format

Share Document