Synthesis of keytones/aldehydes from ethanol formed from E1 (alkoxide reagent)?

In summary, using a tertiary haloalkane with sodium ethoxide and then using the resulting ethanol in an E1 reaction for the synthesis of aldehydes or keytones is possible, but not practical or economical due to the cost of the reagents and the need for additional purification steps. It may be better to simply purchase ethanol or use other methods, such as fermentation, to obtain it.
  • #1
cp-svalbard
8
0
No, this isn't a homework question...

Would it be feasible to use a tertiary haloalkane with sodium ethoxide, then use the ethanol formed from the deprotonation of the haloalkane in the E1 reaction for the synthesis of aldehydes or keytones?

Just thinking it could be an alternative way, since the ethanol formed is usually not the target compound of an E1.

Now that I'm thinking about it, since ethanol is a primary alcohol it would probably be oxidized to a carboxylic acid if you used jones/PCC ??
 
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  • #2
Yes. It is possible for the reactions you stated to occur.
 
  • #3
You could do this, but you might earn a medal for the most wasteful synthesis of the year (no offense intended to you personally, it's a joke!)

Many reactions are possible, but only a select few are used because they are a) economical b) safe and c) practical. Sodium ethoxide is worth much more than ethanol, so you're converting an expensive reagent (actually, two if you're going to waste a tertiary alkyl halide too!) to a cheap reagent. On top of that, you will have to separate your E1 product from your ethanol and then purify your ethanol before you can use it in subsequent reactions. All of this is time, resources, money, and energy, when you could simply buy 95% ethanol and dry it with, for example, magnesium sulfate, to get anhydrous ethanol. Furthermore, the aldehyde and carboxylic acid formed from ethanol, acetaldehyde and acetic acid, respectively, are ALSO very cheap and common reagents. To prepare them yourself serves no real purpose.

If you want to make ethanol, though, maybe the best (and cheapest) way is by hydration of ethylene.

Of course, if you want to minimize waste from reactions, it might be worthwhile to try to recover your ethanol. However, your uses for it will be limited unless you purify it and analyze it. Again, the cost/benefit ratio may not be favorable.

It's nice to do these kinds of reality checks when you're thinking about syntheses :)
 
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  • #4
The easiest way to make ethanol is to ferment sugar with yeast.
 
  • #5


I appreciate your creative thinking and alternative approach to the synthesis of aldehydes and ketones. However, I would caution against using a tertiary haloalkane with sodium ethoxide as it could potentially lead to competing reactions and unwanted side products. Additionally, using jones/PCC for oxidation of ethanol to a carboxylic acid may also result in undesired byproducts.

There are already well-established methods for the synthesis of aldehydes and ketones from ethanol, such as the use of oxidizing agents like chromic acid or potassium permanganate. These methods have been extensively studied and optimized for efficiency and yield. It would be more practical and reliable to use these methods instead of trying to modify the E1 reaction.

Furthermore, it is important to consider the safety and environmental impact of using halogenated compounds in organic synthesis. These compounds can be toxic and harmful to the environment, so it is always best to minimize their use.

In conclusion, while your idea is interesting, there are already established methods for the synthesis of aldehydes and ketones from ethanol that are more practical and efficient. It is always important to carefully consider the potential side reactions and safety implications when designing a synthesis route.
 

What is the purpose of synthesizing keytones/aldehydes from ethanol formed from E1?

The purpose of this synthesis is to convert ethanol, a simple alcohol, into more complex organic compounds known as keytones and aldehydes. These compounds have a wide range of industrial and commercial applications, including use as solvents, flavoring agents, and starting materials for the production of other chemicals.

What is the E1 mechanism and how does it produce ethanol?

The E1 mechanism is a type of elimination reaction in organic chemistry. It involves the removal of a leaving group from a molecule, resulting in the formation of a carbocation intermediate. In the case of ethanol, the leaving group is typically a proton from the hydroxyl group. The resulting carbocation can then react with a nucleophile, such as an alkoxide reagent, to form ethanol.

Why is an alkoxide reagent used in this synthesis?

An alkoxide reagent, such as sodium or potassium ethoxide, is used in this synthesis because it can act as a strong nucleophile, attacking the carbocation intermediate formed in the E1 mechanism. This allows for the formation of ethanol from the starting material and the alkoxide reagent.

What are the key steps in the synthesis of keytones/aldehydes from ethanol formed from E1?

The key steps in this synthesis include the preparation of the starting material, typically an alcohol or alkene, the formation of a carbocation intermediate through the E1 mechanism, and the reaction of the carbocation with an alkoxide reagent to form ethanol. This ethanol can then undergo further reactions, such as oxidation or reduction, to produce keytones or aldehydes.

What are some potential challenges in this synthesis and how can they be addressed?

One potential challenge in this synthesis is the formation of unwanted byproducts, such as alkenes or ethers. These can be addressed by carefully controlling reaction conditions, such as temperature and reaction time, and by using a suitable solvent. Another challenge may be the low yield of keytones/aldehydes, which can be improved by optimizing reaction conditions and purifying the product through techniques such as distillation or chromatography.

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