Cesium tetrafluorocobaltate aromatics

Cesium tetrafluorocobaltate(III) behaves quite differently 12,14 at 250CC it reacts with benzene to give some diene 13 (26%) and several aromatics [fluorobenzene (32%), pentafluorobenzene (9%), perfluorobenzene (4%), and others in lesser amounts]. 

When toluene is fluorinated65 over potassium tetrafluorocobaltate(III), the major products at 330-340cC are notable for being unsaturated and for containing a difluoromethyl group they are also similar in type to those produced in the potassium tetrafluorocobaltate(III)/ben-zene reaction. Over cesium tetrafluorocobaltate(III), toluene and -xylene give66 about 25-30 % of aromatic compounds. 

Cesium tetrafluorocobaltate(III) and quinoline react at 335-350°C to give98 over 60% of a mixture of 11 identified compounds two products 13 and 14 dominate the rest (each was about one-third of the product mixture). The rearranged structure of 14 is quite remarkable at first sight, but its formation resembles that of the polyfluoropyrrolidines from pyridines. Aromatic compounds are not so prominent as products as with other fluorinations over cesium tetrafluorocobaltate(III), but six are formed all have structures analogous to 15, with up to three fluorines on the pyridine ring. 

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