cyclopentanone, KMnO4, and NaOH solution were refluxed until the solution was br

Question

cyclopentanone, KMnO4, and NaOH solution were refluxed until the solution was brown. Manganese Oxide was filtered off, and filtrate was collected and concentrated. Then, it was acidified with 12 M HCl (aq). When acidic, precipitation was initiated with more HCl. The solution was cooled to allow for recrystalization. Small white crystals were formed. Then the solution was left to dry for a week. Then the the IR was taken with a very small amount, and it seems to show no carboxylic acid stretches, no OH peaks, and mo C double bond O stretches. There were small peaks around the sp3 area. The melting point was taken, but the machine went up to 150 degrees celsius without the product melting. The melting point of the theoretical product, glutaric acid, is 98 degrees. The melting point of cyclopentanone is about -52 degrees. There is a small possibility that cyclohexanone was used instead of cyclopentanone. What are all the possibilities that this product could be?

Explanation / Answer

The Inference from the IR:

1. NO Carboxylic Stretches

2. No -C=C- bonds

3. No O stretches

this inferes that the sample doesnt consist of organic compound

Reaction Lead to formation of White crystals:

Here i would like to give series of reactions which are possible:

1. KMnO4 + NaOH O2 + K2MnO4 + Na2MnO4 + H2O

2. 3Na2MnO4 + 4HCl 2NaMnO4 + MnO2 + 4NaCl + 2H2O

3. K2MnO4 + 8 HCl 2 KCl + MnCl2 + 2 Cl2 + 4 H2O

Observations:

i. KCl and NaCl are white crystals with higher melting point ( probability of white crystals )

ii. MnCl2 compounds are pale pink so chances that it might appeared white

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