Radicalar reaction

In this context, an avalanche of studies were devoted to acid-base reactions in their broadest sense (i.e., the Lewis picture), also involving complexation reactions, to the typical organic reactions of addition, substitution, and elimination types, involving nucleophilic and electrophilic reagents including the case of radicalar reactions and excited states (for a review see Ref. [11]) in which our group has... 

Figure 1.9 Radicalar reaction process for demethylation of MeHg under UV radiation. Reproduced with permission of the Royal Society of Chemistry from [51],...

The metathesis reaction of fluorinated alkyl iodides with reagents such as CdMe2 is a well-established procedure for the synthesis of fluoroalkyl cadmium derivatives. A recent application of this method has allowed for the synthesis of compound 186, as shown in Scheme 22.248 This reaction is accompanied by formation of 187, which results from the insertion of the difluorocarbene in the methyl-cadmium bond. Presumably, the difluorocarbene is generated by a radicalar process involving HCF2I and CdMe2. 

TABLE 5. Heat of reaction of basic, radicalar and acidic species on TiCln (in kcal/mol, defined positive when exothermic)... 

The nitrene obtained by photolysis may under certain conditions be highly radicalar, and this method of preparation, likely to cause cross-linking, was avoided. When prepared by a-elimination, carbethoxynitrene reacts with cyclohexene to give a mixture consisting of 85% addition product and 15% various substitution products (13). This reaction was used in attempts to prepare macromolecules with a polyethyleneimine structure. A preliminary investigation showed that the polyisoprenes react to a greater extent than the polybutadienes, and the reaction was first studied on model polyisoprenes. 

A chain polymerization can be radicalar, anionic, cationic, or stereospecific according to the type of initiator used. The reaction may occur in bulk, in suspension, in emulsion, as in solution. It is necessary to choose adequate temperatures for a good control of the processes. 

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