Organic chemistry AS mechanism help!!!

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meemy123
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Hi I am struggling with this question so badly!!! Name:  6A452868-E512-40E6-B83E-754C062128C7.jpg.jpeg
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I reacted propene with HBr to get compound H which turned out to be 2-bromopropane. Then I reacted 2-bromopropane with NaOH and got propene which should be compound I. Not sure how to react propene with acidifed potassium dichromate or perhaps compound I should have been an alcohol. Pls help!!!!
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meemy123
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These are my workings!!! Name:  A8CF479E-FF2E-4B51-916D-9693F23DE072.jpg.jpeg
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MedicPls
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When reacting with NaOH, depending on whether conditions are just aqueous or ethanolic, the bromoalkane can form either an alcohol (if aqueous conditions) or alkene (if alcoholic conditions). In this case it forms an alcohol - this is hinted by the fact that the question later states that compound I reacts with acidified potassium dichromate; acidified potassium dichromate is typically used as an oxidising agent in reactions with alcohols and aldehydes.
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meemy123
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(Original post by MedicPls)
When reacting with NaOH, depending on whether conditions are just aqueous or ethanolic, the bromoalkane can form either an alcohol (if aqueous conditions) or alkene (if alcoholic conditions). In this case it forms an alcohol - this is hinted by the fact that the question later states that compound I reacts with acidified potassium dichromate; acidified potassium dichromate is typically used as an oxidising agent in reactions with alcohols and aldehydes.
Thanks so much for your help!!!!!
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meemy123
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(Original post by MedicPls)
When reacting with NaOH, depending on whether conditions are just aqueous or ethanolic, the bromoalkane can form either an alcohol (if aqueous conditions) or alkene (if alcoholic conditions). In this case it forms an alcohol - this is hinted by the fact that the question later states that compound I reacts with acidified potassium dichromate; acidified potassium dichromate is typically used as an oxidising agent in reactions with alcohols and aldehydes.
When I react propanol with warm acidified potassium dichromate, do i get carboxylic acid or ketone cos it doesn’t say anywhere if its fully or partially oxidised?
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meemy123
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(Original post by MedicPls)
When reacting with NaOH, depending on whether conditions are just aqueous or ethanolic, the bromoalkane can form either an alcohol (if aqueous conditions) or alkene (if alcoholic conditions). In this case it forms an alcohol - this is hinted by the fact that the question later states that compound I reacts with acidified potassium dichromate; acidified potassium dichromate is typically used as an oxidising agent in reactions with alcohols and aldehydes.
I think this is ketone cos its secondary alcohol Name:  80EF8104-A5FA-476E-8111-8BD1E415819D.jpg.jpeg
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MedicPls
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(Original post by meemy123)
When I react propanol with warm acidified potassium dichromate, do i get carboxylic acid or ketone cos it doesn’t say anywhere if its fully or partially oxidised?
If it's a primary alcohol, then under distillation, reacting with acidified potassium dichromate will give an aldehyde. Then under reflux, reacting with acidified potassium dichromate would give a carboxylic acid.

However, if it's a secondary alcohol, then under both distillation and reflux, reacting with acidified potassium dichromate will just give a ketone.

You should note that if it's a secondary alcohol, then it can never be oxidised to a carboxylic acid - only primary alcohols can be fully oxidised to carboxylic acids.

Hope this helps
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