Dissociative Electron Transfer, Substitution, and Borderline Mechanisms in Reactions of Ketyl Radical Anions. Differences and Difficulties in Their Reaction Paths

1997 ◽  
Vol 119 (39) ◽  
pp. 9237-9245 ◽  
Author(s):  
Sason Shaik ◽  
David Danovich ◽  
G. Narahari Sastry ◽  
Philippe Y. Ayala ◽  
H. Bernhard Schlegel
Keyword(s):  
Electron Transfer ◽  
Radical Anions ◽  
Reaction Paths ◽  
Ketyl Radical ◽  
Dissociative Electron Transfer

Paramagnetic organometallic molecules. XIV. Ion-pair and steric effects in dissociative electron transfer reactions of metal cluster carbonyl radical anions

1983 ◽  
Vol 36 (3) ◽  
pp. 441 ◽  
Author(s):  
CM Kirk ◽  
BM Peake ◽  
BH Robinson ◽  
J Simpson
Keyword(s):  
Electron Transfer ◽  
Metal Cluster ◽  
Metal Carbonyl ◽  
Electron Attachment ◽  
Transfer Reactions ◽  
Organic Radical ◽  
Radical Anions ◽  
Dissociative Electron Attachment ◽  
Dissociative Electron Transfer ◽  
Electron Transfer Reactions

An investigation of electron attachment reactions of cluster metal carbonyls is presented. In general, alkyl and organometallic halides react rapidly with metal carbonyl cluster radical anions at ambient temperatures to give the neutral cluster molecule. Halide ion and alkyl or organometallic radicals are also produced, which indicate that these are dissociative electron attachment reactions analogous to those of organic radical anions. The rate of dissociative electron attachment in reactions of PhCCo3(CO)9- was found to depend on the R-X bond energy, the size of the alkyl group and the nature of the counter-ion. In particular, (Ph3P)2N+ retarded some electron transfer reactions to the extent that the bimolecular decay of PhCCo3(CO)9- effectively competed with the electron transfer process in determining the reaction path.

Regioselective S—O vs. C—O bond cleavage in sulfenate ester radical anions

2005 ◽  
Vol 83 (9) ◽  
pp. 1473-1482 ◽  
Author(s):  
Donald LB Stringle ◽  
Mark S Workentin
Keyword(s):  
Electron Transfer ◽  
Bond Cleavage ◽  
Electrochemical Techniques ◽  
Radical Anions ◽  
Peak Potential ◽  
Dissociative Mechanism ◽  
Dissociative Electron Transfer ◽  
Controlled Potential Electrolysis ◽  
Controlled Potential ◽  
Singly Occupied Molecular Orbitals

The electron transfer (ET) reduction of benzyl benzenesulfenate ester (1) and tert-butyl benzenesulfenate ester (2) was investigated using electrochemical techniques. Analysis of the cyclic voltammetry of each compound suggests that the ET reduction proceeds via a stepwise dissociative mechanism. The voltammograms of 1 are similar to those of diaryl disulfides and it was found through controlled potential electrolysis (CPE) product studies that ET reduction leads to S—O bond cleavage. The voltammograms of 2 are dramatically different with a sharper dissociative wave occurring at a more negative peak potential. CPE experiments indicate products that result from ET leading to C—O bond cleavage in this case. DFT calculations of the singly occupied molecular orbitals (SOMOs) of 1 and 2 were performed and offer a rationale for the different reactivity of the two radical anions.Key words: sulfenate esters, dissociative electron transfer, electrochemistry, radical anions.

Sign in / Sign up

Export Citation Format

Share Document