Question

In toluene alkylation
Toleune + CH3Cl- > o-xylene +p-xylene + m-xylene

which is predominant isomerformed in this reaction ? and why?

Answer 1

you would get both the ortho and para positions because alkyl groups are o-,p-directing. Alkyl groups promote substitution at those places because of induction and resonance.

Answer 2

T_T im studying this resonance thingy with Kai and i still don't get it
(btw @Kainui *happy* now i know this reactions also hehe, not resonance tho T_T)

@aaronq do u know any source that has explanation oh how to know which is orth/para or meta directors? ~_~ meaning about resonance thing

Answer 3

hm you could start here: https://www.youtube.com/watch?v=oeX0P1XIEuY

You should try to draw the resonance structures of the ring on your own too.

Answer 4

This one also https://www.youtube.com/watch?v=E9vc9Zmgd1g

Answer 5

this is whats the problem >_<
okay i'll check them out
thnx :*

Answer 6

okay coool

Answer 7

do Deactivators are the ones that take electron
and Activators are the ones that donate electron

Electron donating groups are ortho/para directors
and weakly deactivating halogen is also ortho/para director

Electron taking groups are meta directors/ anything that is more deactivating than halogens are meta directors

okay i get this one
now question

CH3 that attached to benzene ring
where is the electron that is being donated?
or wait


groups like CH3 donate electrons TO electophiles
and groups like NO2 donate their lone pair to the ring itself!!!
hmmm
so when the electron from the group is donated to electrophile- it'll be ortho/para director and activator
and if an electron from the group is donated to the ring itself then its meta director and deactivator

alright idk if im overdoing it ~_~

Answer 8

The CH3 is donating electron density from the C-H \(\sigma\)-bond to the \(\pi\)-system this increases it's nucleophilicity (and ability to attack electrophiles)

It sounds like you have the right idea though

Answer 9

hmmm so its given to pi bond and from there its given to electrophile?

Answer 10

yeah, the electrons from the \(\pi\)-system form the bond to the electrophile.

Answer 11

recall they're not "given", but merely shared

Answer 12

i see (yeah i guessed it'd be shared also since there will be a bond between electrophile and that particular area in the ring)
now about NO2
lone pair is donated to the ring itself this is what i said
now i feel like its not really right

Answer 13

The NO2 group pulls electrons from the \(\pi\)-system,

Take a look at this page and draw the structures on the second picture
http://chemwiki.ucdavis.edu/Organic_Chemistry/Hydrocarbons/Aromatics/Properties_of_Aromatics/Inductive_Effects_of_Alkyl_Groups