Just one sec...
Hey! Sign in to get help with your study questionsNew here? Join for free to post

Chemistry - Benzene

Announcements Posted on
Take our short survey, £100 of Amazon vouchers to be won! 23-09-2016
    • Thread Starter
    Offline

    0
    ReputationRep:
    How do you speed up the halogenation of benzene (benzene + ICl) at room temperature? I need two points, could someone help me with this?

    Thank you very much.
    Offline

    3
    ReputationRep:
    (Original post by Shinjimonkey)
    How do you speed up the halogenation of benzene (benzene + ICl) at room temperature? I need two points, could someone help me with this?

    Thank you very much.
    alow


    Your time to shine?

    I would have thought adding a catalyst would speed it up, same with increasing the volumes of the reagants or conversely increasing the pressure?
    Offline

    3
    (Original post by AngryRedhead)
    alow


    Your time to shine?

    I would have thought adding a catalyst would speed it up, same with increasing the volumes of the reagants or conversely increasing the pressure?
    ICl is a solid or liquid near room temp, so increase the concentration of that if you're working in a solvent. Also you could use a Lewis acid catalyst, one that binds well with Cl, to speed up the iodination of benzene.
    Offline

    3
    ReputationRep:
    (Original post by alow)
    ICl is a solid or liquid near room temp, so increase the concentration of that if you're working in a solvent. Also you could use a Lewis acid catalyst, one that binds well with Cl, to speed up the iodination of benzene.
    Basically everything you say haha

    OP, would you like to join the A-level chemistry whatsapp group we have?

    Shinjimonkey
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by alow)
    ICl is a solid or liquid near room temp, so increase the concentration of that if you're working in a solvent. Also you could use a Lewis acid catalyst, one that binds well with Cl, to speed up the iodination of benzene.
    What kind of catalyst/acid can we use to speed the process? I know if you when you want to react benzene and Br2 you can use FeBr2 as a halogen-carrier catalyst, but what can mix when you are trying to do the halogenation of benzene with ICl?
    Offline

    3
    (Original post by Shinjimonkey)
    What kind of catalyst/acid can we use to speed the process? I know if you when you want to react benzene and Br2 you can use FeBr2 as a halogen-carrier catalyst, but what can mix when you are trying to do the halogenation of benzene with ICl?
    AlCl3 should work well.
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by alow)
    AlCl3 should work well.
    If I was to use AlCl3, how would I get the electrophile? To get the electrophile I+ am I right in saying:
    AlCl3 + ICl -> I+ + AlCL4-
    Offline

    3
    (Original post by Shinjimonkey)
    If I was to use AlCl3, how would I get the electrophile? To get the electrophile I+ am I right in saying:
    AlCl3 + ICl -> I+ + AlCL4-
    Yes that's right.
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by alow)
    Yes that's right.
    Fantastic, thank you very much! If it is ok with you, I would like to ask another thing. I need to turn benzene into iodobenzene by adding I2. It is a similar process but how do you form a good I+ electrophile? is it:
    I2 + HNO3 -> I+ + HNO3I-?
    Offline

    3
    (Original post by Shinjimonkey)
    Fantastic, thank you very much! If it is ok with you, I would like to ask another thing. I need to turn benzene into iodobenzene by adding I2. It is a similar process but how do you form a good I+ electrophile? is it:
    I2 + HNO3 -> I+ + HNO3I-?
    It's this:

    2H+ + 2HNO3 + I2 ---> 2I+ + 2NO2 + 2H2O
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by alow)
    It's this:

    2H+ + 2HNO3 + I2 ---> 2I+ + 2NO2 + 2H2O
    Where do you get the H+ from?
    Offline

    3
    (Original post by Shinjimonkey)
    Where do you get the H+ from?
    Some of the nitric acid molecules will be dissociated, some will not. It's effectively a proton from nitric acid.
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by alow)
    Some of the nitric acid molecules will be dissociated, some will not. It's effectively a proton from nitric acid.
    I see. You are very helpful. Can I ask another question? Promise this will be last. How would you turn iodobenzene into iodo cyclohexane?
    Offline

    3
    (Original post by Shinjimonkey)
    I see. You are very helpful. Can I ask another question? Promise this will be last. How would you turn iodobenzene into iodo cyclohexane?
    I would think you could just use really really high pressure and temperatures hydrogen and a Ni catalyst. I'm not massively sure about that though.

Reply

Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. Oops, you need to agree to our Ts&Cs to register
  2. Slide to join now Processing…

Updated: September 18, 2016
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

Poll
Which would you rather be...?
Help with your A-levels

All the essentials

Rosette

Essay expert

Learn to write like a pro with our ultimate essay guide.

Uni match

Uni match

Our tool will help you find the perfect course for you

Study planner

Create a study plan

Get your head around what you need to do and when with the study planner tool.

Study planner

Resources by subject

Everything from mind maps to class notes.

Books

Essential advice

11 things A-level students wish they'd known before starting their course.

Hands typing

Degrees without fees

Discover more about degree-level apprenticeships.

A student doing homework

Study tips from A* students

Students who got top grades in their A-levels share their secrets

Study help links and info

Can you help? Study help unanswered threadsRules and posting guidelines

Sponsored content:

HEAR

HEAR

Find out how a Higher Education Achievement Report can help you prove your achievements.

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22

Registered Office: International House, Queens Road, Brighton, BN1 3XE

Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.