IDKY
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IGNORE THE TITLE; I meant the structure formula for C4H9Cl NOT C4H7Cl!

There are obviously several isomers, but the question in my book seems to assume that one is more logical than the other, and I don't understand why...

the question is:
Two compounds, A and D, each have the formula C4H9Cl.
Compound A is reacted with dilute aqueous sodium hydroxide to produce compound B with a
formula of C4H10O. Compound B is then oxidized with acidified potassium manganate(VII) to
produce compound C with a formula of C4H8O. Compound C resists further oxidation by
acidified potassium manganate(VII).
Compound D is reacted with dilute aqueous sodium hydroxide to produce compound E with a
formula of C4H10O. Compound E does not react with acidified potassium manganate(VII).
Deduce the structural formulas for compounds A, B, C, D and E
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Claudious
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(Original post by IDKY)
How would you draw the structure formula for C4H7Cl?
Do you mean C4H7Cl or C4H9Cl?
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IDKY
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(Original post by Claudious)
Do you mean C4H7Cl or C4H9Cl?
yess thank you for correcting me! (I meant C4G9Cl)
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Claudious
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(Original post by IDKY)
IGNORE THE TITLE; I meant the structure formula for C4H9Cl NOT C4H7Cl?

There are obviously several isomers, but the question in my book seems to assume that one is more logical than the other, and I don't understand why...

the question is:
Two compounds, A and D, each have the formula C4H9Cl.
Compound A is reacted with dilute aqueous sodium hydroxide to produce compound B with a
formula of C4H10O. Compound B is then oxidized with acidified potassium manganate(VII) to
produce compound C with a formula of C4H8O. Compound C resists further oxidation by
acidified potassium manganate(VII).
Compound D is reacted with dilute aqueous sodium hydroxide to produce compound E with a
formula of C4H10O. Compound E does not react with acidified potassium manganate(VII).
Deduce the structural formulas for compounds A, B, C, D and E



A is secondary chloroalkane, B is secondary alcohol, C is ketone, this can be seen as ketone cannot be oxidised further
D is primary chloroalkane, E is aldehyde, as potassium manganate cannot form a diol as no double C=C bond.
IDKY
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Claudious
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Man I am really bad at answering questions- the chloroalkane can only be primary or secondary. Primary alcohol can only be formed by primary halogenoalkanes and etc.
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IDKY
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(Original post by Claudious)
Man I am really bad at answering questions- the chloroalkane can only be primary or secondary. Primary alcohol can only be formed by primary halogenoalkanes and etc.
The answer in my book claims that A must be a secondary achloroalkane, but what I had in mind was just a straight hydrocarbon chain with the chlorine attached to the end of it (this would be a primary choloralkane) - why is it secondary is what I don't understand :/
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Claudious
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(Original post by IDKY)
The answer in my book claims that A must be a secondary achloroalkane, but what I had in mind was just a straight hydrocarbon chain with the chlorine attached to the end of it (this would be a primary choloralkane) - why is it secondary is what I don't understand :/
When you react a halogenoalkane with dilute aq sodium hydroxide it is a nucleophillic substitution reaction. This means the hydroxide group replaces the chlorine, so if you want a secondary alcohol, the chlorine must be secondary as that is the position that will be replaced.
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Etank
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(Original post by Claudious)
When you react a halogenoalkane with dilute aq sodium hydroxide it is a nucleophillic substitution reaction. This means the hydroxide group replaces the chlorine, so if you want a secondary alcohol, the chlorine must be secondary as that is the position that will be replaced.
I thought D must be tertiary chloroalkane and E is Tertiary alcohol? Only primary and secondary react, and since E doesnt, it has to be tertiary right?
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