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Diels - Alder Rx / HOMO/LUMO?

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OnMyWayThere

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My Orgo teacher taught us the whole Diels Alder reaction but skipped over the section about HOMO / LUMO. Is it important on the MCAT to go and learn all this stuff, or should I be thankful that he skipped it and move on?

Also, anybody know about secondary overlap in Diels - Alder?

Here is what I think, please correct me if I'm wrong:
Secondary overlap is an interaction between the pi bond of the Carbon on the Carbonyl of the dienophile and the pi bond of the diene. Ooh that sounds nasty.
 

Benjo

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you do NOT need to know any of that crap for the MCAT, for goodness sake--relax. Just have a basic idea of what happens in the reaction.
 

OnMyWayThere

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Originally posted by Benjo
you do NOT need to know any of that crap for the MCAT, for goodness sake--relax. Just have a basic idea of what happens in the reaction.

What do you mean relax? My instructor is on that chapter and skipped that stuff and I was wondering if I should read it. CHILL THE *()& OUT!
 

Rendar5

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Originally posted by OnMyWayThere
What do you mean relax? My instructor is on that chapter and skipped that stuff and I was wondering if I should read it. CHILL THE *()& OUT!

You're the one that needs to chill out. He just told you that you don't need to worry about HOMO-LUMO interactions and just need to know the general idea of a Diels-Alder rxn.

edit: don't take that posting as offensive. You're just sounding a bit too high-strung over this. Learn HOMO-LUMO if it helps you make sense of it, but you don't need it to understand the before and after of a basic Diels-Alder.
 

lyragrl

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The Wade textbook has a decent explanation of HOMO and LUMO. I think it's worthwhile to understand it since it makes Diels-Alder sensible. But that's just my opinion...
 

Nuel

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We just covered pericyclic addition reactions (Diels-Alder included). We did learn about about HOMO-LUMO stuff, but it didn't affect the whole learning process. It appears one can get by without it.

N.
 

OnMyWayThere

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Sorry if my previous post was harsh. I guess I was pretty relaxed and asked a simple question but got the response in the wrong way. My bad.

Well it happened that the instructor saved that HOMO/LUMO stuff for tonight and did cover it. Not too bad in my opinion.
 

Gleevec

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Originally posted by OnMyWayThere
My Orgo teacher taught us the whole Diels Alder reaction but skipped over the section about HOMO / LUMO. Is it important on the MCAT to go and learn all this stuff, or should I be thankful that he skipped it and move on?

Also, anybody know about secondary overlap in Diels - Alder?

Here is what I think, please correct me if I'm wrong:
Secondary overlap is an interaction between the pi bond of the Carbon on the Carbonyl of the dienophile and the pi bond of the diene. Ooh that sounds nasty.

No its not important for the MCAT, but it is important for Orgo.

You will likely learn more about HOM orbitals in pchem if you ever take that, but you just need to know that the p orbitals of the pi bonds of the diene and dienophile interact, forming a synthetic product with the double bond in the intermediate position of the diene (between where the double bonds in the diene used to be). More or less, the molecular orbital stuff just relates to the orbitals electrons are in during the transition state, allowing for the generation of the synthetic alkene product. There are some decent animations of this online that you could probably search for, but I wouldnt stress too much about the molecular orbitals, just know what he explains, its fairly complex and most of it isnt covered til pchem anyway.
 

UCLAstudent

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Diels-Alder has been asked on the MCAT in the past, so it's worth knowing. I'm not sure how HOMO/LUMO relates to it, though.
 

exmike

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The orgo on the MCAT is so basic that any decent prep course is all you need if you're somewhat familiar with it. I wouldn't worry about it.
 

Brickhouse

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Originally posted by exmike
The orgo on the MCAT is so basic that any decent prep course is all you need if you're somewhat familiar with it. I wouldn't worry about it.


yeah, I teach O-chem for a test prep and I don't even remember what homo/lumo is. well...my brother is a homo, but I don't think it has anything to do with diels-alder.
 

exmike

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Originally posted by Brickhouse
yeah, I teach O-chem for a test prep and I don't even remember what homo/lumo is. well...my brother is a homo, but I don't think it has anything to do with diels-alder.

:laugh: :laugh:

i love it!
 
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