Benzodithiophene analogues

Halogens on a benzodithiophene quinone analogue can be metallated by lithium. The resulting lithio compounds react with borate esters, eventually allowing conversion to the unhalogenated system <83CL905>. 

The same type of disconnection (Scheme 17.34) was utilized for the synthesis of the thio analogue 176 of furostifoline 177, where the central toluene ring was constructed by subjecting diene intermediate 178, formed liom 179, to the 2-Ru catalyst [59]. For a related example resulting in the formation of benzodithiophenes, see the following paper by Stephenson and coworkers [60]. 

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