Base-promoted radical coupling

Base-promoted radical coupling between an aryl diazonium salt and an arene to form a diaryl compound. 

Glucose oxidase, as protein-based redox probe, 1, 909 Glutamate analogs, lead triacetate arylation, 9, 391 Glutarates, via tin hydride-promoted radical coupling,... 

Deprotonation of the primary amine group by the addition of a base promotes head-to-tail coupling of aromatic amine radical cations. When the base diphenylguanidine is added to solutions of the 9-amino-lO-phenylanthracene radical cation one obtains the dimer ... 

Metal-based reagents are often used to promote one- and two-electron oxidations of arenols. Radical-mediated C-0 coupling reactions of aryloxy radicals can, of course, lead to ortho-quinol derivatives, but the preparative value of such an approach is poor and essentially limited to intramolecular cases. For example, certain bis-phenols such as 36a-c have been spiroannulated in good yields by diradical C-0 coupling under favorable one-electron oxidation regimes (Figure 12) [65-67]. 

Ketyls generated by the reaction of SmE with aldehydes and ketones have been incorporated into numerous sequential processes in which a radical reaction is involved. Sequential radical processes, radical cyclization/carbonyl additions, radical cyclization/substitution reactions, nucleophilic acyl substitution/radical cyclizations, cyclization/elimination processes, and others have all been realized. Because these types of reactions have been extensively reviewed [2b, 25], further details will not be given here. Needless to say, new sequential processes based on SmE-promoted ketyl/olefin coupling reactions are still being developed (Eq. 75) [88]. 

Chem. Descrip. 3-Methaciyloxypropyl trimethoxysilane CAS 2530-85-0 EINECS/ELINCS 219-785-8 Uses Coupling agent for free-radical crosslinked polyester, rubber, polyolefins, styrenics, acrylics adhesion promoter for solv., water-based, solventless, arid powd. coating systems pigment treatment Properties Sp.gr. 1.040 vise. 2 cSt flash pt. (CC) 46 C 100% act. 

---