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Topic: Why does the solution start at Vinyl?  (Read 6254 times)

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Offline _Weirdo_0.o

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Why does the solution start at Vinyl?
« on: October 15, 2012, 09:32:22 PM »
I thought you go in alphabetical order?

Offline _Weirdo_0.o

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Re: Why does the solution start at Vinyl?
« Reply #1 on: October 15, 2012, 09:35:36 PM »
Also, why did he start there anyways?  I understand if a double and triple bond are tied you start with double, but I don't see the tie....

Offline _Weirdo_0.o

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Re: Why does the solution start at Vinyl?
« Reply #2 on: October 15, 2012, 09:40:56 PM »


Why is the answer b?

Offline EpicWinston

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Re: Why does the solution start at Vinyl?
« Reply #3 on: October 15, 2012, 10:26:57 PM »
Acidity is based off: electronegativity, direction of equilibrium, stableness of  conjugate base, and atomic radius.

Since b is the most electronegative atom, it is also the most acidic

Offline _Weirdo_0.o

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Re: Why does the solution start at Vinyl?
« Reply #4 on: October 15, 2012, 10:35:24 PM »
Acidity is based off: electronegativity, direction of equilibrium, stableness of  conjugate base, and atomic radius.

Since b is the most electronegative atom, it is also the most acidic
You're so helpful.
So... why'd he start at the vinyl?

Offline EpicWinston

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Re: Why does the solution start at Vinyl?
« Reply #5 on: October 15, 2012, 11:38:34 PM »
For your first question, I am not 100% sure, but I am guessing that your professor started with vinyl because it was a double bond that allowed the numbers to be the smallest. And the order that you write the names are alphabetical (you never count the prefixes like di-)

Offline _Weirdo_0.o

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Re: Why does the solution start at Vinyl?
« Reply #6 on: October 15, 2012, 11:45:41 PM »
But it's a V! hahaa
I even tried adding up the numbers to be smaller and I found a different way... maybe I'll just go talk to him -___-

Offline EpicWinston

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Re: Why does the solution start at Vinyl?
« Reply #7 on: October 15, 2012, 11:57:44 PM »
Vinyl is written last on the actual written name (that's where alphabetical rule comes in ex 26 diBromo, tert Butyl  it is written in alphabetical order), and remember that it should be the smallest sum of number that include all of the double bonds. I am not 100% sure though lol. You should talk to him

Offline _Weirdo_0.o

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Re: Why does the solution start at Vinyl?
« Reply #8 on: October 16, 2012, 12:04:37 AM »
Epic Winston does not know what to do!?  :o

Offline Dan

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Re: Why does the solution start at Vinyl?
« Reply #9 on: October 16, 2012, 04:59:22 AM »
The numbering is based on lowest locants in the the parent ring: 1,5,7,11-cyclooctacosatetraen-3,9,15-triyne

[note IUPAC name is cyclooctacosa-1,5,7,11-tetraen-3,9,15-triyne]
My research: Google Scholar and Researchgate

Offline _Weirdo_0.o

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Re: Why does the solution start at Vinyl?
« Reply #10 on: October 16, 2012, 08:21:55 AM »
The numbering is based on lowest locants in the the parent ring: 1,5,7,11-cyclooctacosatetraen-3,9,15-triyne

[note IUPAC name is cyclooctacosa-1,5,7,11-tetraen-3,9,15-triyne]
But why is 1 part of the parent ring?  Isn't it a substituent 'cause it's not in the ring?

Offline DrCMS

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Re: Why does the solution start at Vinyl?
« Reply #11 on: October 16, 2012, 08:39:51 AM »
The numbering is based on lowest locants in the the parent ring: 1,5,7,11-cyclooctacosatetraen-3,9,15-triyne

[note IUPAC name is cyclooctacosa-1,5,7,11-tetraen-3,9,15-triyne]
But why is 1 part of the parent ring?  Isn't it a substituent 'cause it's not in the ring?

There is a double bond between C1 and C2, C5 and C6 etc etc.  There is also a vinyl substituent on C1

Offline _Weirdo_0.o

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Re: Why does the solution start at Vinyl?
« Reply #12 on: October 16, 2012, 09:05:12 AM »
The numbering is based on lowest locants in the the parent ring: 1,5,7,11-cyclooctacosatetraen-3,9,15-triyne

[note IUPAC name is cyclooctacosa-1,5,7,11-tetraen-3,9,15-triyne]
But why is 1 part of the parent ring?  Isn't it a substituent 'cause it's not in the ring?

There is a double bond between C1 and C2, C5 and C6 etc etc.  There is also a vinyl substituent on C1
Ohkay, I know why it starts with vinyl. I actually answered my own question last night and didn't realize it till now >_>
When a triple and double bond are tied for closest position to the end, the double bond always wins.  Even if it starts with a v!

Offline Dan

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Re: Why does the solution start at Vinyl?
« Reply #13 on: October 16, 2012, 09:26:14 AM »
The vinyl substituent is irrelevant. The numbering would be the same regardless of the identity of the substituent at position 1.

The numbers are assigned on the basis of the locants of the endocyclic double and triple bonds in the parent ring, not on the basis of the substituents.
My research: Google Scholar and Researchgate

Offline EpicWinston

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Re: Why does the solution start at Vinyl?
« Reply #14 on: October 16, 2012, 03:31:00 PM »
Lol, I am flattered. The following posts are saying what I tried to say

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