A new methodology for the preparation of fluoroaromatic compounds based on fluorinated dihalocarbenes and polyhaloolefins as building blocks

A new general methodology has been developed for the synthesis of diverse fluoroaromatic compounds based upon the utilization of fluorohalocarbenes and fluorinated polyhaloolefins as fluoro-containing building blocks, on the one hand, and unsaturated or polyunsaturated cyclic or acyclic compounds (cyclopentadiene and its derivatives, indenes, allylbenzenes, styrenes and acyclic 1,3-dienes), on the other hand. In most cases, the process can occur as one or two step reaction involving sequential cycloaddition, isomerisation with ring expansion, and aromatisation accompanied by dehydrohalogenation. Examples of the use of the resulting fluoroaromatic compounds for the preparation of important biologically active compounds are presented.