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Reduction Reactions watch

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    I am a bit confused about the reduction
    reactions of aliphatic and aromatic compounds.


    I know when the aliphatic ones are
    reduced if it has carboxylic acid and ketone group

    it redeuces to give 2 alcohol groups
    under reflux.So all groups are reduced.


    However I was taught that when you have
    aromatic compound/

    benzene that has lets say carboxylic
    acid group and nitro group attached to it


    does not reduce to alcohol, instead
    nitro group reduces only and I don't get why that's the case.

    Is there a method to tell which and how
    many
    functional groups are going to be
    reduced in an aromatic compound if you have complex
    compound that has too many functional
    groups? So I am very confused with this

    any helps will be appreciated.
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    (Original post by Merdan)
    I am a bit confused about the reduction
    reactions of aliphatic and aromatic compounds.


    I know when the aliphatic ones are
    reduced if it has carboxylic acid and ketone group

    it redeuces to give 2 alcohol groups
    under reflux.So all groups are reduced.


    However I was taught that when you have
    aromatic compound/

    benzene that has lets say carboxylic
    acid group and nitro group attached to it


    does not reduce to alcohol, instead
    nitro group reduces only and I don't get why that's the case.

    Is there a method to tell which and how
    many
    functional groups are going to be
    reduced in an aromatic compound if you have complex
    compound that has too many functional
    groups? So I am very confused with this

    any helps will be appreciated.
    depends on the reducing agent, some are strong some are weak.

    strong: LiAlH4 in dry ether

    weak: NaBH4 in alkaline medium or ethanol
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    (Original post by Coral Reafs)
    depends on the reducing agent, some are strong some are weak.

    strong: LiAlH4 in dry ether

    weak: NaBH4 in alkaline medium or ethanol
    When methylglyoxal is reduced by
    “strong” LiAlH4 both ketone and aldehyde

    groups are reduced. Also when it is
    reduced by “weak” Tollen's reagent or

    NaBH4 both groups are also reduced and
    sometimes just one group is reduced and

    not the other I still dont see the
    limitations which probably going to
    confuse in an exam as well...
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    (Original post by Merdan)
    When methylglyoxal is reduced by
    “strong” LiAlH4 both ketone and aldehyde

    groups are reduced. Also when it is
    reduced by “weak” Tollen's reagent or

    NaBH4 both groups are also reduced and
    sometimes just one group is reduced and

    not the other I still dont see the
    limitations which probably going to
    confuse in an exam as well...
    on my board which was edexcel, aromatic ring compounds used Tin with HCl has the reducing reagent in the markschemes, but LiAlH4 in dry ether aswell as NaBH4 in ethanol was also acceptable too. there are a few others which you could probs find on chemguide(google it) or docbrowns' website. but in the textbooks i used, LiAlH4 was the popular one.

    I think you get into specifics of reducing agents when u study first year chem or something.
 
 
 
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