Acetyl Ferrocene (shown below) is an aromatic organometallic compound that can b
ID: 960110 • Letter: A
Question
Acetyl Ferrocene (shown below) is an aromatic organometallic compound that can be prepared using the reaction scheme shown below. Often time in this reaction two products form, acetyl ferrocene and diacetyl ferrocene. If a scientist wanted to synthesize in lab acetyl ferrocene using this reaction a purification technique such as column chromatography is usually employed to purify and isolate the desired product. The column chromatography typically used has alumina as the stationary phase and the mobile phase used has a gradient. First 100% hexanes is used to evaluate the first band then the mobile phase is changed to 50/50 mixture of dichloromethane and hexanes to evaluate the two remaining bands. Assuming the reaction did not go to completion and starting material is present in addition to the two product, which fraction should the scientist keep if the desired compound is acetyl ferrocene? Explain your answer.Explanation / Answer
Acetylation on Ferrocene is the nonpolar product formation and the diacetyl formation becomes more nonpolar product.
The compound spots on TLC plate can be seen first(top spot or nonpolar) is the Di acetyl, second spot(top to second one) is the mono acetyl (Desired) and the polar (top to third) is the starting material Ferrocene.
From the column (normal phase column cromatography) nonpolar spot (top) elutes first, then second spot elutes. The second fraction is collected as a desired compound.