Tentacled Iron Sandwiches

Abstract

A sixfold alkyl chain extension, the reaction of 1 with tBuOK and H2CCHCH2Br in THF to give 2, was achieved in one step in quantitative yield. The FeII center of 2 can be completely and reversibly reduced but not oxidized (with Br2). Instead, bromine adds in a 1,3 fashion to all terminal CC bonds. The hexaalkylbenzene ligand can be released from 2 by irradiation. [Fe] = [(η5-C5H5)Fe]⊕.