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What's an easy way to prepare cyclohexanone if I dont have direct access to cyclohexanol? I'm willing to synthesize cyclohexanol from more common materials, then make cyclohexanone from that. But most of the instructions for one cyclohexano- say to start with the other cyclohexano-.

I'm looking to start with common materials and synthesize cyclohexanone or cyclohexanol. If i have cyclohexanol, i can use bleach and acetic acid to make cyclohexanone.

Since I dont have access to lab deliveries at the current moment, what are the most common chemicals to start with to make this happen? AKA, stuff I can order legally online without a lab cert.

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    $\begingroup$ Can you access chloro or bromocyclohexane? $\endgroup$
    – Waylander
    Apr 1 '20 at 7:24
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    $\begingroup$ Radicalic bromination of cyclohexane, the one common alkane where this leads to just one product. $\endgroup$
    – Karl
    Apr 1 '20 at 7:51
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    $\begingroup$ I can access potassium bromide and small amounts of cyclohexane. If it matters, i own a centrifuge as well (cheap, 4000 rpm max) $\endgroup$ Apr 3 '20 at 16:14
  • $\begingroup$ Found this: slader.com/discussion/question/… $\endgroup$ Apr 3 '20 at 16:16
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    $\begingroup$ Why are you doing this? Cyclohexanone is available commercially. 2L is less than $100. It's kind of a waste of time and money to try to make it... $\endgroup$
    – Zhe
    Apr 10 '20 at 17:29
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Do you have access to phenol? If you have, then use that to make cyclohexanol (hydrogenation of phenol using nickel catalyst):

enter image description here

Then treat cyclohexanol with copper(II) and chromium(III) oxides to convert it to corresponding ketone (Dehydrogenation):

enter image description here

Benzene could work as a starting material but the reaction might be costly and hectic as the catalyst is not a household item$\ce{^{[2]}}$. Secondly, it is used as a starting material in the synthesis of nylon and the reaction intermediate is a mixture of cyclohexanol and cyclohexanone(mixed oil)$\ce{^{[3]}}$ which add to your task of separating them. Better convert it to phenol$\ce{^{[4]}}$.

Notes and References

  1. http://www.leck.co.uk/demo/eci3/polymers/polyamides.html (above reaction synthesis source). It is a part of polyamide synthesis

  2. https://link.springer.com/article/10.1023/B:CATL.0000011080.03035.eb

  3. http://www.greener-industry.org.uk/pages/nylon/4nylonpopup.htm

  4. https://www.quora.com/What-is-the-method-to-convert-benzene-to-phenol

  5. https://russianpatents.com/patent/220/2205819.html

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  • $\begingroup$ Meta comment about phenol: I think it is not wrong to (still) use the Thiele ring here provided one keeps in mind that it symbolizes the six delocalized $\pi$ electrons. The Kekulé-pattern as if there were $\ce{C=C}$ double and $\ce{C-C}$ single bonds in benzene (known to represent one mesomeric formula only) however has the advantage to count the $\pi$ electrons in question exactly. It is too easy to draw two Thiele cycles in the formula of naphthalene and to think «2 Thiele rings with 6 $\pi$ electrons each = 12 in total», while the Kekulé formula shows there are only 10 of them. $\endgroup$
    – Buttonwood
    Apr 7 '20 at 14:46
  • $\begingroup$ What machine do I use to run a reaction at 5 atmospheres, lol? A pressure cooker only gets to 1.02 atm.... $\endgroup$ Apr 16 '20 at 4:54
  • $\begingroup$ @nick Making cyclohexanone requires good quality catalyst and somewhat drastic conditions. If you aren't able to achieve such conditions which I am sure you won't in household environment, you can always purchase cyclohexanone. Also, I believe that the collective price for reagents, catalysts and equipments used for making cyclohexanone will definitely surpass the price of cyclohexanone itself. $\endgroup$ Apr 16 '20 at 6:33
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There exist different approaches to synthesize cyclohexanol and/or cyclohexanone from cyclohexane. One method is to use O2 and Vanadium oxides at 400°C and 15 atmospheres. Another method is to oxidize with H2O2 at 80°C with a catalyzer made from Silica gel treated by a silicone derivates holding an amino drop at the end of the alkyl chain fixed on Si. The so obtained amino-catalyzer is then treated by eosin, and then with copper ions, before being used to oxidize cyclohexane. I doubt these processes can be used easily for producing small amounts of cyclohexanol or -one in an ordinary lab.

Another approach is starting from phenol, that gets reduced by H2. This is the way DuPont produces cyclohexanol which is then oxidized by HNO3 and converted into adipic acid, before being then copolymerized with hexanediamine for synthesizing nylon.

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    $\begingroup$ It would be much better if you could cite the sources. It would be really a great answer if you do that.. $\endgroup$
    – Zenix
    Apr 1 '20 at 13:25
  • $\begingroup$ My source was my organic course I took a long time ago, without any reference ! $\endgroup$
    – Maurice
    Apr 1 '20 at 14:40
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    $\begingroup$ Not directly relevant to the question, but FYI: although phenol reduction is used commercially, it was never the primary route to cyclohexanol for adipic acid production by Dupont. The majority was produced by cyclohexane oxidation (cf this 1994 EPA report:www3.epa.gov/ttn/chief/ap42/ch06/bgdocs/b06s02.pdf). Current production data is available in this report if you have a subscription: ihsmarkit.com/products/… $\endgroup$
    – Andrew
    Apr 4 '20 at 12:46
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Well as u said you have access to cyclohexane then oxidation of cyclohexane in the presence of oxygen yield a mixture of cyclohexanol and cyclohexanone.You can add a good oxidizing agents such as Pyridinium chlorochromate or potassium dichromate as per availability increase the yield of cyclohexone (as ketones dont get easily oxidised).

Reference: 1)http://www.greener-industry.org.uk/pages/nylon/4nylonpopup.htm 2)https://www.researchgate.net/post/What_is_the_mechanism_of_the_oxidation_of_cyclohexane_like_What_are_the_most_common_products 3)https://en.wikipedia.org/wiki/Oxidation_of_secondary_alcohols_to_ketones 4)https://www.chemguide.co.uk/organicprops/alcohols/oxidation.html

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