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    why racemic mixture of 2-methyl-1-phenyl-1-butanone is formed when (R)-(+)-2-methyl-1-phenyl-1-butanone is dissolved in acidic solution?
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    (Original post by tan71500)
    why racemic mixture of 2-methyl-1-phenyl-1-butanone is formed when (R)-(+)-2-methyl-1-phenyl-1-butanone is dissolved in acidic solution?
    I imagine that you mean

    C6H5COCH(CH3)CH2CH3

    The chiral center is starred below:

    C6H5COC*H(CH3)CH2CH3

    At low pH the keto group can easily tautomerise to the enol, making the chiral carbon sp2 and subsequent keto formation can result in either enantiomer forming.

    C6H5COC*H(CH3)CH2CH3 <--> C6H5COH=C*(CH3)CH2CH3
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    It’s not at a terminal position because there’s a phenyl on carbon 1 - I’m pretty sure that 2-methyl-1-phenyl-1-butanone is entirely correct (PhCOCH(CH3)CH2CH3).

    Actually as you’ve written it 2-methylphenylbutanone is pretty ambiguous, the methyl could be on the phenyl ring and you haven’t specified where the phenyl is attached on the carbon backbone.

    It’s a pretty good example why IUPAC naming is useless after a point though, not that easy for a human or a computer to understand...

    (Original post by charco)
    The molecule as described does not exist.

    You cannot have a ketone with the carbonyl at position 1. It would be an aldehyde.

    I imagine that you mean 2-methylphenylbutanone, C6H5COCH(CH3)CH2CH3

    The chiral center is starred below:

    C6H5COC*H(CH3)CH2CH3

    At low pH the keto group can easily tautomerise to the enol, making the chiral carbon sp2 and subsequent keto formation can result in either enantiomer forming.

    C6H5COC*H(CH3)CH2CH3 <--> C6H5COH=C*(CH3)CH2CH3
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    (Original post by KombatWombat)
    It’s not at a terminal position because there’s a phenyl on carbon 1 - I’m pretty sure that 2-methyl-1-phenyl-1-butanone is entirely correct (PhCOCH(CH3)CH2CH3).

    Actually as you’ve written it 2-methylphenylbutanone is pretty ambiguous, the methyl could be on the phenyl ring and you haven’t specified where the phenyl is attached on the carbon backbone.

    It’s a pretty good example why IUPAC naming is useless after a point though, not that easy for a human or a computer to understand...
    I was using phenylethanone as my reference and now see that the chain length alters the issue.
    I stand corrected and have edited my post accordingly.
 
 
 
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