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A few Destroyer OC questions...

Discussion in 'DAT Discussions' started by yankees27th, Jan 5, 2009.

  1. yankees27th

    7+ Year Member

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    #153: Choice B says that if 2 compounds boil within a few degrees of one another, a fractional distillation would be used for separation. I thought you can't do fractional distillation if bp's are close. If I'm wrong, does anyone know what I'm thinking of?

    #170: The question deals with Gabriel synthesis...which I've never heard of. Is it just one of those "Destroyer-going-into-too-much-detail" questions or is this something I should know?

    #184: Same concern as with question 170, except with Dieckmann condensation. This one I at least vaguely remember from class though...

    Thanks guys. DAT only about 2 weeks away, yikes! :scared:
     
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  3. doc3232

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    You can't do a regular distillation, but a fractional will work. Just make the tube longer and through in some aluminum. A high enough distillation tube (don't know name), distillation will work correctly.

    heard of Gabriel, but no idea what it is. Same thing with Diekmann.
    I heard only basic reactions are on test, but I will not risk it. Probably will learn them all.
     
  4. jalpari02

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    agree with doc3232 about the distillation.

    my ochem teacher focused on the Gabriel Synthesis quite a bit, so I know what it is, but I don't think you need to know exactly what it is on the real thing. just know the reaction and the reagents and products roughly, i'm sure that'll be okay.

    and I've never heard of Dieckmann...but I have heard of acetoacetic ester synthesis...seems a little similar..but not quite.
     
  5. joonkimdds

    joonkimdds Senior Member
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    I heard of dickmenn and gabriel from orgo2. I think I still have them in my classnotes. I will look for it.
     
  6. yankees27th

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    Thanks for the distillation help! As for the other two reactions, I guess I'll just learn them. For the Gabriel synthesis the reactant is pretty distinct-looking so it shouldn't be too hard to recognize (here's the wiki page for the reaction if anyone wants it: http://en.wikipedia.org/wiki/Gabriel_synthesis). As for Dieckmann, I've learned it before. I'll just have to work on familiarizing myself with it more...
     
  7. Sublimation

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    As for the distillation. Its called simple distillation. And it is used with 2compounds of boiling point diff of >10 degrees. As for fractional you will used a fractional column to distill. Which if i remember correctly is basically packed with a copper sponge.
     

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