Iron → HCID 5148332, compound

Participants

Reaction Steps

25.00 g (204.6 mmol) of 1,2,4,5-tetramethyl-cyclopenta-1,3-diene (HMe4Cp) was charged into a reaction vessel and dissolved in approximately 200 ml of hexane while under positive nitrogen pressure. The solution was cooled with an ice bath to approximately 0° C., whereupon 84 ml (210 mmol) of 2.5M n-butyllithium was charged into the reaction vessel via syringe. Next, the reaction mixture was allowed to warm to room temperature while being agitated overnight. In a separate vessel, 1.95 g (35 mmol) of Fe in approximately 100 ml of tetrahydrofuran (THF) was purged with nitrogen and then cooled to 0° C. 11.56 g (70 mmol) of FeCl3 was charged into the Fe/THF mixture in 3 equal portions, whereupon the mixture was heated to reflux for approximately 2 hours under a nitrogen atmosphere. The FeCl2-2THF was then cooled to room temperature, and transferred to the LiMe4Cp suspension via cannula. The complete mixture was heated to reflux for 2 hours. After cooling, the reaction was quenched by the addition of approximately 300 ml of water and a small amount of zinc powder. The reaction mixture was charged into a separatory funnel, whereby the organic layer was isolated and collected. The aqueous layer was extracted with Et2O. Next, the organic layers were combined, washed with a saturated brine solution, dried over MgSO4, and filtered. The solvents were then removed by rotary evaporation to give an orange solid which was washed with MeOH and collected on a vacuum frit. Additional product was recovered by reducing the volume of the MeOH solution and cooling in a freezer overnight. The total yield was approximately 22 g of octamethylferrocene.

Provenance & Evidence