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    Can somebody please explain to me the answer to this question clearly, I am having so much trouble understanding it. First of all what is the question asking for, why is it the N atom, not others and also why is is the circled N atom, not the one next to it.

    My understanding of the question is which atom will a hydrogen ion be added onto? Is that a correct understanding? Could you please explain what the question means and how to arrive at the answer. Thank you so much.

    Question:
    "On the structure in your answer booklet, circle the atom in loperamide which will be
    protonated in the salt. "

    Answer:
    'See attachment in link'

    https://www.dropbox.com/s/aqcizz2itu...9Q4a.docx?dl=0

    Thank you!!
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    (Original post by champion1)
    Can somebody please explain to me the answer to this question clearly, I am having so much trouble understanding it. First of all what is the question asking for, why is it the N atom, not others and also why is is the circled N atom, not the one next to it.

    My understanding of the question is which atom will a hydrogen ion be added onto? Is that a correct understanding? Could you please explain what the question means and how to arrive at the answer. Thank you so much.

    Question:
    "On the structure in your answer booklet, circle the atom in loperamide which will be
    protonated in the salt. "

    Answer:
    'See attachment in link'

    https://www.dropbox.com/s/aqcizz2itu...9Q4a.docx?dl=0

    Thank you!!
    Your understanding is correct, protonation means adding a hydrogen ion.

    It goes to the nitrogen because it has an available lone pair of electrons.

    The other nitrogen is part of an amide group which is less basic due to the lower availability of the lone pair which conjugates with the pi system of the carbonyl group. Protonation would disrupt the molecular orbital delocalisation and is unfavourable
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    (Original post by charco)
    Your understanding is correct, protonation means adding a hydrogen ion.

    It goes to the nitrogen because it has an available lone pair of electrons.

    The other nitrogen is part of an amide group which is less basic due to the lower availability of the lone pair which conjugates with the pi system of the carbonyl group. Protonation would disrupt the molecular orbital delocalisation and is unfavourable

    (Original post by charco)
    Your understanding is correct, protonation means adding a hydrogen ion.

    It goes to the nitrogen because it has an available lone pair of electrons.

    The other nitrogen is part of an amide group which is less basic due to the lower availability of the lone pair which conjugates with the pi system of the carbonyl group. Protonation would disrupt the molecular orbital delocalisation and is unfavourable
    Thanks for your reply!
    Is my understanding right that the phenyl groups/benzene rings can't be deprotonated because that would disrupt the ring structure so it can only be substituted?
    Also doesn't the O of the C=O carbonyl, O of O-H and Cl have lone pair as well, so why can't the hydrogen go onto that?
    Also if the hydrogen goes to the N in the answer, wouldn't the N have more than three bonds so be +ve?
    Am I right in saying that the N in the answer is a tertiary amine?

    I understand the part about the lone pare of amide conjugating with pi. Sorry for so many questions!!
    Thanks!
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    (Original post by champion1)
    Thanks for your reply!
    Is my understanding right that the phenyl groups/benzene rings can't be deprotonated because that would disrupt the ring structure so it can only be substituted?
    If you remove a hydrogen atom from the ring you would need to make a triple bond whose bond angles would be constrained to 120 degrees. This is too strained.

    (Original post by champion1)
    Also doesn't the O of the C=O carbonyl, O of O-H and Cl have lone pair as well, so why can't the hydrogen go onto that?
    Not all lone pairs are sufficiently basic to accept protons.


    (Original post by champion1)
    Also if the hydrogen goes to the N in the answer, wouldn't the N have more than three bonds so be +ve?
    Clearly if you add H+ to N you are going to have a positively charged group.

    (Original post by champion1)
    Am I right in saying that the N in the answer is a tertiary amine?
    yes

    (Original post by champion1)

    I understand the part about the lone pare of amide conjugating with pi. Sorry for so many questions!!
    Thanks!
    No problem
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    Thanks for this! I understand now.
 
 
 
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