View Full Version : Vinyl vs. allyl groups
What is the difference between a vinyl (ethenyl) and an allyl group? I read the wikipedia explanation of an allyl group but I couldn't make much sense of it.
Is an allyl group just a terminal vinyl group meaning a vinyl group with nothing attached to the second carbon apart from a H?
When people say allylbenzene do they refer to a particular compound or a group of compounds that have a benzene ring and an allyl group? For example is propenylbenzene an allylbenzene? Theres no wikipedia entry for propenylbenzene. Are there any other names for it? I tried phenylpropene but nothing either.
FullMetalJacket
2008-06-24, 00:48
An allyl group is a vinyl group bearing an extra methylene on the non-terminal end of the chain.
I drew a picture!
http://www.mediafire.com/imageview.php?quickkey=2x06dttmrm3&thumb=4
Ah I get it now. Thanks. Fucking hell they're some well drawn diagrams fknut.
Ah I get it now. Thanks. Fucking hell they're some well drawn diagrams fknut.
Oh good!
And yes, I'm very talented... ;)
Took me about 20 minutes to draw this one for my website
http://toxicopoeia.com/plantsofthegods/chemistry/chemicals/harmine/harmine_mol.gif
Harmine. Thank god it wasn't heroin I had to draw.
I never understood what these dotted lines meant
http://upload.wikimedia.org/wikipedia/commons/thumb/7/7b/Heroin-2D-skeletal.png/220px-Heroin-2D-skeletal.png
those and squiggly lines what do they mean?
DiamondX
2008-06-25, 21:09
The dotted and thick lines mean it is a 3D structure and the molecules are coming towards you or away from you. I don't remember which is which though.
Took me about 20 minutes to draw this one for my website
Chemdraw ftw!
I never understood what these dotted lines meant
those and squiggly lines what do they mean?
These are just ways to represent the stereochemistry of a molecule - the dashed bonds are pointing back behind the plane of the page, and the bold ones are pointing towards you.
When people say allylbenzene do they refer to a particular compound or a group of compounds that have a benzene ring and an allyl group? For example is propenylbenzene an allylbenzene? Theres no wikipedia entry for propenylbenzene. Are there any other names for it? I tried phenylpropene but nothing either.
Particular compound--allylbenzene is C6H5-CH2CHCH2. If you change the C6H5 for an OH, you'll get the allyl alcohol that wiki talks about. Allyl is just a propenyl with the dbl bond on the 2nd carbon; phenylpropene is also a compound, but with the dbl bond on the 1st rather than the second carbon as in allylbenzene.
This is illustrated excellently by the (trans) propenyl isomer: http://en.wikipedia.org/wiki/Anethole
...and the allyl isomer: http://en.wikipedia.org/wiki/Estragole
Alternatively you could call 1-phenylpropene isoallylbenzene (provided you specify which isomer, of course :mad:).