Thiophen Analogues of Indene and Fluorene

The interest in the thiophen analogues of fluorene is continuing. A detailed paper on the synthesis of (343) and (344) and the nitration of the latter has now appeared. On treatment of (343) and (344) with Mo(CO)s or W(CO)s, (345) and (346) are obtained. From (347) and (348), the thiophen-selenophen fluorenone analogues (349) and (350) were obtained by Ullmann coupling.  

Fulvalene analogues such as (345) and (346) were also prepared in the more classical way, by treating the fluoreny 1-lithium analogue with the fluoren me 

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