A convenient synthetic approach to bis-functionalised quaterfluorenes

Ni(COD)(2) promoted coupling of bromofluorenes functionalised with boronic esters or trimethylsilyl groups proves to be an efficient method for the preparation of reactive bifluorenes, which are key intermediates for the synthesis of bis-substituted oligofluorenes. The synthetic method has been exploited as a key step for the synthesis of a chiral 2,7'''-diiodo-quaterfluorene and a 2,7'-bis-amino quaterfluorene. (C) 2004 Elsevier Ltd. All rights reserved.