Bulk Synthesis of Octa- and Nonamethylfluorene (Flu‘ ‘H and Flu*H) and the Characterization of the Organometallic Derivatives Flu*SnMe<sub>3</sub>, [(FeCp)<sub>2</sub>Flu*H][PF<sub>6</sub>]<sub>2</sub>, and [(FeCp)<sub>2</sub>Flu‘ ‘H][PF<sub>6</sub>]<sub>2</sub>
作者:James Moss、Jemima Thomas、Andrew Ashley、Andrew R. Cowley、Dermot O'Hare
DOI:10.1021/om0603666
日期:2006.8.1
The large-scale synthesis of two highly methylated fluorene ligands is reported, and the synthesis and characterization of three organometallic derivatives are reported. Starting with 1,2,3,4-tetramethylbenzene, 1,2,3,4,5,6,7,8-octa- and 1,2,3,4,5,6,7,8,9-nonamethylfluorene (Flu"H and Flu*H) have been synthesized in overall yields of above 50%. Both fluorenes may be deprotonated at the 9 position to yield useful organometallic synthons; the Sn derivative, Flu*SnMe3, is synthesized using this reagent, and its molecular structure has been elucidated. The Fe bimetallics [(FeCp)(2)Flu*H][PF6](2) and [(FeCp)(2)Flu"H][PF6](2) have been isolated, and their electrochemical properties ascertained. Electrochemical measurements on these complexes show the methylated fluorene ligand acts as a strong electron donor and acts to increase the electronic communication between the metal centers, in comparison with the nonmethylated analogues. The solid-state structure of [(FeCp)(2)Flu"H][PF6](2) has been determined and, unlike the Sn complex, does not show a significantly twisted fluorenyl core.