mani93786
Badges: 11
Rep:
?
#1
Report Thread starter 1 year ago
#1
Is it 3-chloropropene or 3-chloroprop-1-ene?
0
reply
liam.ro
Badges: 11
Rep:
?
#2
Report 1 year ago
#2
It's 3-chloropropene.

Since there are three carbons in propene, there are only two places where you can have a C=C double bond. However, both C=C bonds will include a terminal carbon bond, so will both be 3-chloroprop-1-ene. (Another way to think about it is, the two possibilities are identical because flipping one molecule sideways will result in the other.) Hence, because both variations are essentially the same positional isomer, we call it propene without the need to specify carbon number.
0
reply
mani93786
Badges: 11
Rep:
?
#3
Report Thread starter 1 year ago
#3
(Original post by liam.ro)
It's 3-chloropropene.

Since there are three carbons in propene, there are only two places where you can have a C=C double bond. However, both C=C bonds will include a terminal carbon bond, so will both be 3-chloroprop-1-ene. (Another way to think about it is, the two possibilities are identical because flipping one molecule sideways will result in the other.) Hence, because both variations are essentially the same positional isomer, we call it propene without the need to specify carbon number.
Thanks! But would you then have to specify where the double bond is if there is a functional group of a higher priority, i.e. O-H or C=O? For example prop-1-en-1-ol or prop-2-en-1-ol.
0
reply
liam.ro
Badges: 11
Rep:
?
#4
Report 1 year ago
#4
(Original post by mani93786)
Thanks! But would you then have to specify where the double bond is if there is a functional group of a higher priority, i.e. O-H or C=O? For example prop-1-en-1-ol or prop-2-en-1-ol.
Nope, you wouldn't have to because prop-2-ene doesn't exist. So because prop-1-ene is the only possibility, you only ever need to refer to it as propene.
0
reply
mani93786
Badges: 11
Rep:
?
#5
Report Thread starter 1 year ago
#5
(Original post by liam.ro)
Nope, you wouldn't have to because prop-2-ene doesn't exist. So because prop-1-ene is the only possibility, you only ever need to refer to it as propene.
You didn’t answer my question. I’m asking what if there’s an alcohol group attached to it? The alcohol would get the priority and hence the carbon attached to the O-H group would be C1. So then wouldn’t you have to number the position of the double bond? If on C1 or C2.
0
reply
liam.ro
Badges: 11
Rep:
?
#6
Report 1 year ago
#6
(Original post by mani93786)
You didn’t answer my question. I’m asking what if there’s an alcohol group attached to it? The alcohol would get the priority and hence the carbon attached to the O-H group would be C1. So then wouldn’t you have to number the position of the double bond? If on C1 or C2.
My bad. In that case, yes, its exactly the way you just put it. Since the prioritised alcohol group is given a carbon number, you must also specify the position of the C=C bond; C1, C2 or C3.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

If you haven't confirmed your firm and insurance choices yet, why is that?

I don't want to decide until I've received all my offers (55)
39.57%
I am waiting until the deadline in case anything in my life changes (24)
17.27%
I am waiting until the deadline in case something in the world changes (ie. pandemic-related) (6)
4.32%
I am waiting until I can see the unis in person (14)
10.07%
I still have more questions before I made my decision (15)
10.79%
No reason, just haven't entered it yet (12)
8.63%
Something else (let us know in the thread!) (13)
9.35%

Watched Threads

View All