Hardest OChem Subject

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OnMyWayThere

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I'm in the middle of the semester and taking OChem 1... First test was easy but man, this stuff is getting HARD. What was your hardest subject in OChem 1? We're on SN1 and SN2 / E1 / E2 and it's HARD. Is this the easy stuff? What was your worst part of the first semester? I'm SERIOUSLY worried.... I thought I had it made with the first half and now it's like WHOA. thanking you in advance!

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orgo is great like that. you always think what youre doing is really hard....that is until you get to the next section, which is always much harder. then you wish for the easy stuff that you used to think that was hard. i have no clue if that makes sense, but it will when youre studying for that last exam 2nd semester. good luck.

ps. everything first semester is easy, relatively speaking. what a sooooprise
 
My prof calls Sn2/Sn1/E1/E2 the beginning of the end-- If you haven't kept up, or didn't understand what we were doing before, and somehow got away with m____izing (a forbidden word in our class) the material, that you're screwed. In his words, of course.
 
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organic 1 was hard, here at UD the averages are always in the D range, but then organic 2 was much easier. i feel like in organic 1 you learn all the concepts and then in organic 2 you have to apply them all.
 
Originally posted by vixenell
My prof calls Sn2/Sn1/E1/E2 the beginning of the end-- If you haven't kept up, or didn't understand what we were doing before, and somehow got away with m____izing (a forbidden word in our class) the material, that you're screwed. In his words, of course.

I love it...m__izing is the forbidden word, but then the prof says things like..."Don't m__ize, just keep working through the problems again and again making sure you know what is going on each step (where everything is moving), then you will understand the material"...sounds like rote m__ization to me...hahah I just think denouncing m__ization and calling it something else is the fad these days.

I love in, in my Endocrinology class my prof told us that "YES! You will have to MEMORIZE things in this class. I know you and other profs think it is cool to pretend like you don't, but I am telling you that you will". That class is the best.

YOU AREN'T COOL UNLESS YOU PEE YOUR PANTS!!
 
/edit - if you tell us what specifically you're having trouble with, we can give more help

Organic gets conceptually difficult when you start looking at things in 3 dimensions: stereochemistry.

My advice (and this is one of the few things I actually took my own advice on):

Get a molecule model kit if you don't have one. Make your cyclohexane and twist it into the different conformations. Stare it at until you can see the entire structure in your head in every conformation. Draw it and parts of it (ie just a 1 carbon or 2 carbon stretch) in every conformation with the different drawing methods (saw-horse, etc). Put some non-hydrogens onto the ring and re-draw, especially with flips between the conformations. Is that alcohol group axial or equatorial?..

I may be misinterpreting what you're having difficulty with, but for me, nailing the 3d stuff early on was the best thing I ever did in organic. Then, as you learn SN1/SN2/E1/E2, you can apply what you learn about how electronegativity, nucleophiles/electrophiles, and other chemical properties to a solid spatial understanding.
 
Yeah, the Sn2, E2 etc reactions are nothing compared to Orgo II.

Its not that it gets harder, the number of reactions just increases exponentially. I mean just the reactions with carboxylic acid derivatives (one chapter of my orgo book) are more reactions than I learned all of Orgo I. Be sure you learn the basics well, though. It'll pay off (at least thats what everyone says).

Good Luck:clap:
 
I can honestly say that I thought that the SN1/SN2/E1/E2 was easy, but took a solid beating when it came to Wittig, Michaelson-Morley, Claisen condensation, etc. Just pray that you teacher doesn't get into HOMO/LUMO and molecular orbital theory.

I made a mistake getting too comfortable at the beginning of the semester, and took a beating by the end. My suggestion is to study up on resonance structures and electron withdrawing vs. electron donating groups NOW, as they are central to everything else.

Brace yourself, and good luck.
 
Those of you that know me on here know I don't gloat, but I thought O-chem was easy. If you have a the ability to picture things 3-d then your going to do ok.

As far as the hardest Orgo subject, Polycyclic Aromatic Hydrocarbon Chemistry. Forget everything you learned and start over, err!
 
Wow... I wake up to such great remarks and advice. Thank you very much.

How do you guys memorize for Organic? I mean,I understand memorizing the rules (SN2 needs good leaving group, bad this...) but how can memorize a bunch of reactions?

Stereochem was a breeze for me. I had no problems with it. I guess when the instructor throws problems worth 50% of the test saying this ring reacts with this molecule, what are all the products and which are major/minor.... that gets me worried. Hopefully, after this weekend with putting in 15 hours, I well get that 1 chapter.... :mad:
 
I thought O-Chem was fun, except for the impossible synthesis problems. Given a starting molecule, some reagents, and an ending molecule, and we had to figure out how to get from start to end.
 
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do all the questions in the chapter and at the end of every chapter multiple times...u should have all the reactions down pat by then

visualizing molecules sucks, get the model kit or just try and wing it :)
 
The best way to ace ochem is by taking practice tests. Go on any search engine and type in something like "organic chemistry I (or II) practice exams". You will be amazed at all of the exams out there on professors web sites from around the country. Just bookmark the good sites and take the exams for practice. By the time I took an organic exam I had taken a dozen plus practice exams. As a result I aced every exam in organic while the averages were in the fifties. Try it, it works.
 
Ochem can be tough at times, but it's good to have this for upper-level classes in Biochem, Cell &Developmental Bio, Molecular, and Microbial Genetics. Ochem does not get tougher...if anything it gets easier because the same concepts of steric hindrance, rate, NMR, etc...will show up in your study of other reactions too (just like how you're studying for the SN1/SN2/E1/E2 reactions).

Try re-writing your notes into one sheet of paper! That's all you should have in studying for these reactions. If you have more than 1 sheet, you're making it more complicated than it has to be.
 
personally I found Orgo easy and fun. Understand the concepts of orgo I and orgo II should be breeze. I found orgo II easier than I. The one aspect of orgo that gave me problems (still does) was the concept of chirality on a saw horse projection.
 
sn1/sn2 and e1/e2 are all about how you think about them...

For example, here's one way of looking at sn1/sn2 reactions that isn't at all painful. Similarly, this might help you see that e1/e2 is actually kind of... fun... and maybe even kind of... sexy! :eek: :love:

It'll be over before you know it, might as well amuse yourself.

Nanon
 
That was seriously the hardest I have laughed off of anything online. Being that I take this so seriously and reading this relationship about lesbianity, cheating girls and backside attack in a 3some related to OChem was amusing! Thanks for sharing that... The instructor made it pretty clear today. Basically said, if it is a strong acid, then it's SN2 or E2 (if weak, then SN1/E1). Then look at if the Halogen is on a primary/sec/tert carbon. And then you make the distinction between SN2 or E2. Easy as that! At least for this instructor.

That website was seriously great though for entertainment purposes :laugh: :laugh: :laugh: :laugh: :clap:
 
If you remember the tune (and words) to the Mickey Mouse Club March (the one that goes M-I-C-K-E-Y-M-O-U-S-E), then sing along to this. Click here for midi: http://www.geocities.com/Broadway/Stage/7840/Mickeyms.mid


If you have an alcohol but want a halide, then
S-N-1 R-E-A C-T-I-O-N
Take off the OH group and put on halogen
S-N-1 R-E-A C-T-I-O-N
HCl! (For Cl!) HBr! (For Br!)
And hydroiodic acid for I-I-I-I!
Come along and substitute and we shall sing again:
S-N-1 R-E-A C-T-I-O-N

First the acid gives is proton to the oxygen.
S-N-1 R-E-A C-T-I-O-N
Water leaves and what's left is a carbocation.
S-N-1 R-E-A C-T-I-O-N
It won't last! (It won't last!) What it does! (What it does!)
Is add on the ion of a hali-i-i-ide!
Halide is the nucleophile in substitution
S-N-1 R-E-A C-T-I-O-N

This reaction's really fast with tertiary ion.
S-N-1 R-E-A C-T-I-O-N
Secondary will need heat, harsher conditions then.
S-N-1 R-E-A C-T-I-O-N
Primary! (Hardly works!) You need heat! (Lots of heat!)
The acid must be HBr or H-I-I-I.
And the mechanims is concerted. That is when
S-N-2 R-E-A C-T-I-O-N
 
If you remember the song Waterloo by Abba
http://www.bun.ru/midi/midi_mid_archive/Abba/Waterloo.mid

My my! In SN2, the rate law is second order,
Oh yeah! The step thats rate determining has two reactants in:
The leaving groups still attached while
Attacked by the nucleophile

SN2! Nucleophile joins as old bond breaks,
SN2! Two partial bonds in transition state;
SN2! Sterically best with few alkyl groups,
SN2! Rate law is raised to the power two.
Whoa, whoa, whoa whoa, SN2 - primary halides go SN2!

My my! Inductively, no hope for primry halides -
Oh yeah! One electron-releasing alkyl group to stabilise:
Theres no carbocation here
(Not stable enough, it appears)

SN2! Nucleophile joins as old bond breaks,
SN2! Two partial bonds in transition state;
SN2! Sterically best with few alkyl groups,
SN2! Rate law is raised to the power two.
Whoa, whoa, whoa whoa, SN2 - primary halides go SN2!

Theres no carbocation here
(Not stable enough, it appears)

SN2! Sterically best with few alkyl groups,
SN2! Primary halides go SN2,
Whoa, whoa, whoa, whoa, SN2 - primary halides go SN2!
Oo-oo-ooo-ooh, SN2 - primary halides go SN2,
Whoa, whoa, whoa, whoa, SN2 - primary halides go SN2!
 
Wittig Reaction

Beverly Hillbillies theme song
http://anothertime.com/MIDIS/bevhillb.mid

Suppose you want an alkene from ketones or aldehyde
Just mix trisphenylphosphene with a good alkyl halide.
The phosphorus attacks the carbon by an SN2,
And carbon frees the bromine--it's the only thing to do!

If you call this a reagent, it's your own darn fault;
Mixing these together gives you nothing but a salt.
But add a little BuLi for an ylide you can use,
In tetrahydrofuran, there's no way that you can lose.

The ylide bites the carbonyl--the slickest thing you've seen,
The oxygen turns negative, it's half a betaine.
But then the whole thing falls apart, the phospho just lets go,
And latches on to what it can (it double bonds the O!)

When all is said and done we've got an alkene in the tube,
And all this time we thought that Dr. Wittig was a rube!
But if we don't count E / Z, then we get a perfect yield,
No wonder Dr. Wittig was outstanding in his field!
 
Did you seriously sing these songs to yourself durinig exams? This stuff is hilarious! Thanks for sharing it. You're lucky people to be done with OChem. It's all good though... we work hard, we play hard and we will be rewarded hard in the near future.
 
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