1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: 3C2H2 + Cu2Cl2 and more

  1. Jun 12, 2007 #1
    1)I cant find what will happen if 3C2H2 reacts with Cu2Cl2 . C6H6 cant be , or does it ?
    2) after several reactions i got unknown compound which reacts with 2NaNH2(in the ether ) and product is C6H4 . How it can be C6H4 ? Does anybody know what unknown compound can be ?
  2. jcsd
  3. Jun 20, 2007 #2
    If I am doing this right, 3C2H2 in Cu2Cl2 will give you one molecule of unreacted C2H2 and vinyl ethyne, or CH2-CH-CCH, which if you add up all the carbons and hydrogens, you get 6C and 6H.

    As to the second question, I don't think C6H4 exists, but it is listed as a hypothetical byproduct in some benzene-related reactions. Imagine a six-carbon chain where all of the carbons are double bonded and the end carbons each have two hydrogens, and you have C6H4. I think it would be called 1,2,3,4,5-pentahexene or something like that. However, I don't think you could get that from a reaction with Na-NH2 or any other strong base (NaOH, NaH, etc.).
  4. Jun 21, 2007 #3


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Benzyne is a derivative of benzene or a substituted benzene. Some of these derivatives of benzene can be driven to produce benzyne by the action of a strong base such as sodium amide. It is not a six-carbon chain at all but rather a six-carbon ring. You must figure out why TWO molecules of sodium amide are required to produce the benzyne.

    I'll give you a hint: if chlorobenzene were reacted with ONE molecule of sodium amide, benzyne (C6H4) could be produced (base-assisted dehydrohalogenation).
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook