Organometallic processes, electron transfers

The fluorination of organometallics with Al-fluoroamide reagents has received Only limited attention. Grignard reagents, both aliphatic and aromatic, are converted to organofluonne compounds. Both the electron transfer and the Sf,j2 ntechamsms have been considered in these processes [SO, 81, 82], The reactions 0 exemplified in equation 46 [48, 69, 70, 71, 75] Organosilanes are also fluonnated [71] (equation 47)... 

Electrochemistry, organic, structure and mechanism in, 12, 1 Electrode processes, physical parameters for the control of, 10, 155 Electron donor-acceptor complexes, electron transfer in the thermal and photochemical activation of, in organic and organometallic reactions. 29, 185 Electron spin resonance, identification of organic free radicals, 1, 284 Electron spin resonance, studies of short-lived organic radicals, 5, 23 Electron storage and transfer in organic redox systems with multiple electrophores, 28, 1 Electron transfer, 35, 117... 

Section 3, are commonly classified as inner-sphere (contact) ion pairs (Kochi, 1988). Accordingly, in organic and organometallic processes a strong distinction must be made in their behaviour from that of other less common outer-sphere ion pairs that are pertinent to the Marcus treatment of electron-transfer dynamics (Eberson, 1987 Lee et al., 1991). 

The organometallic compounds of the group I and II metals are strongly basic and nucleophilic. The main limitation on alkylation reactions is complications from electron-transfer processes which can lead to radical reactions. Methyl and other primary iodides usually give good results in alkylation reactions. HMPA can accelerate the reaction and improve yields when electron transfer is a complication.64... 

In the mid-1960s, Dessy and coworkers [12, 13] provided an extensive survey of the anodic and cathodic reactions of transition metal organometallic species, including binary (homoleptic) carbonyls, and this provided a stimulus for many later detailed studies. Whereas the electrochemistry of heteroleptic transition metal carbonyls is covered elsewhere in this volume, that of the binary carbonyls, which is covered here, provides paradigms for the electrochemistry of their substituted counterparts. A key aspect is the generation of reactive 17-electron or 19-electron intermediates that can play key roles in the electrocatalytic processes and electron-transfer catalysis of CO substitution by other ligands. 

One-electron transfer processes are rather common in the reactions of Group I and II organometallic reagents with substrates, including alkyl halides, R —X, and unsaturated organic acceptors, A (113) ... 

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