6 OCHEM destroyer questions

[113zami]

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I was hooping someone can help me with these

1) why is this called benzaldehyde, a benzyl group should have a CH2 group outside the ring, which this one doesn't have, instead this one is a phenyl group so why isn't it called phenylaldehyde?
http://i274.photobucket.com/albums/jj243/113zami/benzaldehyde.jpg

2) In some of destroyer answers like #29 they have (+)and (-) in front of the answer what is referring to…enantiomers??

3) What does reflux in organic chemistry mean?

4) #8 destroyer does this reaction also work the same way with the other halogens or only the Cl2? I could not find this reaction in my text

5) #13destroyer is choice D meta directing?


6) Between tertiary non allylic and secondary allylic carbocation which one is more stable?

7) what's the advantage of a Soxhlet extractor? I know how it functions but don't understand what's the advantage of using it
thanks

 

[TexasDent]

1.) That is just what benzaldehyde is, look at it on wikipedia. But I do understand what you are saying.
3.) Reflux just means letting the reaction take place over heat. Usually a steam bath.
6.) I believe that allylic always trumps normal so I am almost positive that a secondary allylic would be more stable than a tertiary normal carbocation.
7.) The advantage of the Soxhlet extractor is that instead of a lot of portions of warm solvent being passed through the sample, just one batch of solvent is continuously recycled to continue to dissolve and concentrate the solution.

Sorry I do not have Destroyer so I can't help you with the others.

 

[113zami]

for the first one, what I mean is imagine a benzyl group, it's composed of the conjugated ring plus a CH2 group coming out of it, now imagine a phenyl group, its just composed of the conjugated ring with no CH2 group coming out of it, so since there is no CH2 group between the aldehyde and the conjugated ring in benzaldehyde, then this should be a phenyl group not a benzyl group, so why are we calling it benzaldehyde it's not a benzyl group, its a phenyl group

i ask because i need to know when I can call a substituent phenyl or benzyl, i have always learned that a CH2 group off of the ring is called benzyl and the same ring without the ch2 is called phenyl so now when i see a ring without the ch2 called benzyl i get confused

 

[doc3232]

I was hooping someone can help me with these

1) why is this called benzaldehyde, a benzyl group should have a CH2 group outside the ring, which this one doesn't have, instead this one is a phenyl group so why isn't it called phenylaldehyde?
http://i274.photobucket.com/albums/jj243/113zami/benzaldehyde.jpg

2) In some of destroyer answers like #29 they have (+)and (-) in front of the answer what is referring to…enantiomers??

3) What does reflux in organic chemistry mean?

4) #8 destroyer does this reaction also work the same way with the other halogens or only the Cl2? I could not find this reaction in my text

5) #13destroyer is choice D meta directing?


6) Between tertiary non allylic and secondary allylic carbocation which one is more stable?

7) what's the advantage of a Soxhlet extractor? I know how it functions but don't understand what's the advantage of using it
thanks

1) Ok, I see what your saying. It isn't benzyl aldehyde. It is benzaldehyde.
See what I am saying? benzaldehyde doesn't say it has a benzyl group in it. just like benzene doesn't have the CH2 on it.
2) +/- is its optical rotation. how it turns the light.
3) Reflux is heating in a round bottom while have a water condenser attached to the top. You do this so the gases that come out of the liquid (due to the heat) condense back into the flask and continue reacting.
4) I don't have Destroyer, but some reactions will only work certain halogens. Depending on their size/electronegativity (It is complicated and I don't know if you should memorize which do what).
5) If it is electron withdrawing (any carbox, nitro, nitrile groups will make it meta.)
6) I would say secondary allylic, Resonance always dominates when it comes to stability.
7) never heard of it

Finally, half the questions you asked could have been checked on wikipedia...
I am bored though, and hence I don't mind 🙂