Acetylferrocene Synthesis and Electroanalysis

Synthesis:

• 1.49g Ferrocene dissolved in 5 mL acetic anhydride in 100 mL r.b.f. with stir bar.
• Stirred at r.t. on dry-syn block, hotplate with temperature probe.
• 1.5 mL phosphoric acid added over 2 minutes (solution turns red).
• Heated at 50 °C for 10 minutes, left to cool.
• Tracked with TLC. One drop into vial of 2 mL 1:4 Et₂O:petrol (40-60) + 1 mL 2 M sodium acetate.
• Solution poured into 150 mL 2M sodium acetate.
• Washed with Et₂O (3 x 50 mL).
• Saturated NaHCO₃ to organic layer until bubbling stops.
• Dried with MgSO₄.
• Rotary evaporated. Crude - 1.42 g.
• Column with wide-bore setup with 200 micron silica and 4-5 mL toluene. Eluted with 1:5 Et₂O:Petrol.
• Initial yellow band discarded.
• Product rotary evaporated. Product - 0.36 g, 19.7% yield.
• Acetylferrocene is an orange powder!!

Notes:

• Be gentle while dissolving the ferrocene initally. Can easily not react if stuck on the sides of the flask.
• Try not to get acetylferrocene powder on your skin. Apparently they can absorb through and cause brain damage?? Wish my professor had told me that...

Voltammetry:

• 1 mg Fc into 1 ml butyronitrile + 50 μL perchloric acid.
• 20 μL onto gold electrode.
• Three different scan rates cyclic voltammogram measured.
• Square-wave voltammogram measured.
• 1 mg product in 1 mL butyronitrile + 40 μL perchloric acid.
• Same measurements.

CV Settings

• t eq = 5 s
• E begin = -0.2 V
• E vertex 1 = 0.6 V
• E vertex 2 = -0.2 V
• E step = 0.01 V
• Scan rate = 0.1, 0.25, 0.5 V/s

SW settings

• t eq = 5 s
• E begin = 0.6 V
• E end = -0.2 V
• E step = 0.01 V
• Amplitude = 0.1 V
• Freqency = 20 Hz