Oxidation with Sodium Hypochlorite

final weight percent yield 2,4-DNP Tollen's test pathway

.42g 67% positive negative oxidation of secondary OH

Good Things

My experiment went well. I began my experiment with .64g of

2-ethyl-1,3-hexanediol. The molecular weight of this compound is 146.2g/mol. It is converted into 2-ethyl-1-hydroxyhexan-3-one. This compounds molecular weight is 144.2g/mol. This gives a theoretical yield of .63 grams. My actual yield was .42 grams. Therefore, my percent yield was 67%. This was one of my highest yields yet. I felt that this was a good yield because part of this experiment is an equilibrium reaction. Hypochlorite must be used in excess to push the reaction to the right. Also, there were better ways to do this experiment where higher yields could have been produced. For example PCC could have been used. However, because of its toxic properties, its use is restricted. The purpose of this experiment was to determine which of the 3 compounds was formed from the starting material. The third compound was the oxidation of both alcohols. This could not have been my product because of the results of my IR. I had a broad large absorption is the range of 3200 to 3500 wavenumbers. This indicates the presence of an alcohol. If my compound had been fully oxidized then there would be no such alcohol present. Also, because of my IR, I know that my compound was one of the other 2 compounds because of the strong sharp absorption at 1705 wavenumbers. This indicates the presence of a carbonyl. Also, my 2,4-DNP test was positive. Therefore I had to prove which of the two compounds my final product was. The first was the oxidation of the primary alcohol, forming an aldehyde and a secondary alcohol. This could not have been my product because the Tollen’s test. My test was negative indicating no such aldehyde. Also, the textbook states that aldehydes show 2 characteristic absorption’s in the range of 2720-2820 wavenumbers. No such absorption’s were present in my sample. Therefore my final product was the oxidation of the secondary alcohol. My final product had a primary alcohol and a secondary ketone

Bad Things

I really don’t have that many bad things to write about. I forgot to shake my sep funnel after my first addition of dichloromethane. I had to redo that step. Also, there is a very slight chance that a little bit of dichloromethane could have been left in my final product. When I was distilling, I thought I had boiled away everything in my flask. The dichloromethane distilled at 39.5 degrees. To avoid distilling to dryness, I removed the heat. However, there was still some product left. I just couldn’t see it very easily. I believe that most of the dichloromethane that was left after removing the heat was eventually removed while the flask was cooling. Also, I would like to have seen my ketone absorption a little higher in wavenumber. As stated in the book, an unknown at an absorption of 1750 wavenumber almost certainly is a ketone. The absorption of my ketone was at 1705. It could have been influence by something else. Perhaps it could have been dichloromethane. My yield could have been improved by being more careful with my washes. If I had been much more careful while separating layers, I could have had more product. This would have taken more time however.