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    Structural isomerism and stereoisomerism should be considered when answering this question.

    If a molecule contains two non-identical chiral carbon atoms, four optical isomers exist. How many isomers are there with

    ● molecular formula C7H14O and
    ● a five-membered ring and
    ● a tertiary alcohol group? A)4 B)5 C)9 D)13

    Answer is C)9, WHY?
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    Please help
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    This is the first isomer I found. (How many chiral centres are there?)
    Name:  Isomer 1.png
Views: 58
Size:  23.8 KB
    This is the second isomer I found. (How many chiral centres are there?) Ofc, there is one more that I will let you find yourself
    Attached Images
     
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    (Original post by _JB_)
    This is the first isomer I found. (How many chiral centres are there?)
    Name:  Isomer 1.png
Views: 58
Size:  23.8 KB
    This is the second isomer I found. (How many chiral centres are there?) Ofc, there is one more that I will let you find yourself
    Is it possible for you to display it as structural formula, these images confuses me, thanks
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    Here you go.
    Name:  Isomer 1.png
Views: 56
Size:  15.4 KB
    Attached Images
     
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    Name:  Isomer 2.png
Views: 57
Size:  20.1 KB
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    (Original post by _JB_)
    Name:  Isomer 2.png
Views: 57
Size:  20.1 KB
    Name:  擷取.PNG
Views: 51
Size:  31.7 KB

    This is the third isomer I could find, is this correct?
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    (Original post by _JB_)
    Here you go.
    Name:  Isomer 1.png
Views: 56
Size:  15.4 KB
    isnt this structure incorrect? the 2nd carbon has 5 bonds.
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    Name:  IMG_20180411_170850.jpg
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    (Original post by ROadmanKys)
    isnt this structure incorrect? the 2nd carbon has 5 bonds.
    Just accident, remove one of hydrogen will do the trick.
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    (Original post by ngwengsamowo)
    Name:  擷取.PNG
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    This is the third isomer I could find, is this correct?
    BDunlop has the correct answer above. The answer you wrote is not a tertiary alcohol, it is an ether.
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    Thanks a lot
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    From the ER: "The structure should start with a cyclopentyl
    ring with an OH group and a methyl group on carbon atom 1. There is one carbon atom left to add.
    Cambridge International Advanced Subsidiary and Advanced Level
    9701 Chemistry June 2017
    Principal Examiner Report for Teachers
    © 2017

    If this carbon atom goes on carbon atom 2 of the ring as a methyl group we have a molecule with two
    chiral centres and therefore four isomers.

    If this carbon atom goes on carbon atom 3 of the ring as a methyl group we have a molecule with two
    chiral centres and therefore four more
    isomers, making eight so far.

    If this carbon atom goes on the methyl group already
    attached to carbon atom 1 this becomes an ethyl
    group. This molecule is not chiral, giving one more isomer, making nine. "
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    Why isnt the last molecule a chiral? I dont get it
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    The cyclic structure will be symmetrical. Thus it is not optically active. So no chiral carbon.
 
 
 
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