Monday, October 6, 2008

Studying for My Organic Chemistry Test


It's that time again where I labor mentality all night to cram for one test...ORGANIC CHEMISTRY! I have confidence this time considering it is the second time I am taking it; however, it never hurts to study a bit earlier and have more time to do other important tasks later. So let's note this : 8:23 a.m., organic chemistry cramming time.
Nomenclature:

1. Determine the longest chain: decane
2. Determine how to number: starting from the left to right (cyclohexane comes before methane in alphabetical order)
3. List all the substituents:
2-cyclohexane
3-t-butyl
4-propane
5-bromo
6-isopropyl
7-sec-butyl
9-methane
4. Put it all together in alphabetical order:
5-bromo-3-t-butyl-7-sec-butyl-2-cyclohexane-6-isopropyl-9-methyl-4-propyldecane


Name the following compound; identify substituents as axial or equatorial; less or more stable chair form (Green = Cl):
Let's name this compound: where should I start? Well, we have a methane substituent and chloro substituent. We don't know where to start numbering so let's start with alphabetical. C comes before M so Chloro is before Methane, so let's start numbering from there. There's two ways to number them:



Hmm...we always number where it is the least amount. So, the one on the left hand is correct. If they both were the same distance from each other, then it wouldnt matter which way we number the chain, it would still be the same thing.
So the name of this cycloalkane is trans-1-chloro-3-methylcylcohexane. Trans because both substituents are not pointing the same way.
Now the axial and equatorial position: axial is when the substituent points directly up or down, and equatorial is when the subsituent slants up or down. Looking at this structure, Methane is in the axial position while Chloro is in the equatorial position.
So is this chair form less or more stable? Well, to determine that, I would flip the ring:
-------------------->
The conformation on the left hand side is less stable because the methane has three hydrogens attached making it more bulky than the Chloro. The protruding hydrogens are closer in distance to the adjacent hydrogens; therefore, it creates more repulsion thus causing it to be less stable.

Stereoisomers:
I would say this is the difficult part of this chapter. But let's get it started:
1. Stereogenic center:
The one on the left has a stereogenic center, the one on the right does not. With the left, there's 4 different substituents while the right only has 3 different substituents (Note: I'm not being technical, this is just my shortcut of learning).


2. R and S configuration: This strcuture has an R configuration. Remember, the lowest substituent has to be going away while the higher substituent needs to come toward you (this is based on their atomic number; higher atomic number has higher priority). If it's hard for you to see it in this configuration, let's just spin the CH3, Br and H to the right and let's see what we'll get:

As you can see, the numbering goes clockwise (to the right) so it is an R configuration.
How many stereogenic centers? 1

How many possible stereoisomers (2^n stereoisomers)? 2^1 = 2

Why isnt the 2nd carbon from the left a stereogenic center? Because it has only 3 different substituents (note: the two methyl groups are the same).

Why isn't the alkene a stereogenic center? Because it is sp2 hybridized, stereogenic centers are only on sp3 hybridized carbons.
.
Why is the alkene number 1? Because we can treat the double bonds as individual single bonds. Basically, that alkene carbon is bonded to two other carbons, and one of those two other carbon is bonded to another CH3. So that has a higher priority because of the amount of carbons (basically 4 carbons total on that side). The number two has its priority because it is bonded to two other carbons and the number 3 only has CH3. It's not reasonable to determine the R and S configuration because there's no 3-D configuration.

3. Chirality
Chiral: mirror images that are not superimposable.
Achiral: mirror images that are superimposable.

This image would be chiral because no matter how much you try to spin the three molecules on the bottom, you can't get the same exact molecule again. One of them would still be out of place. To me, anything that has 4 different substituents usually is chiral. This would also be known as enantiomers (nonsuperimposable mirror images).

4. Diastereomers and Meso compounds.
Diastereomers: stereoisomers that are not mirror intakes.
Meso compound: achiral compound with stereogenic center.
Let's try to get this to be the same

These two are diastereomers because if u spin the carbon number 3 so that the OH would be on the same side, the 3-D configuration would be different. The OH on carbon number 3 would be going away while the one on number 2 would be going toward you, so that would not give you the same configuration. (Note: Disregard the 2R,3R on the second image.)
This is a meso compound because you can rotate carbon 3 or 2 180 degrees and be able to get the same molecule. They are definitely the same molecule so they count as 1 not 2.

Tartaric acid should have 2^2 = 4 stereoisomers, but in reality it only have 3 since two of them are meso to each other.

5. Racemic mixture = 50:50 mixture of two enantiomers.

6. Properties of enantiomers:
S and R compounds has the same melting point, boiling point, density and TLC. However they have different Specific Rotation, S has a + rotation while R has a - rotation.

It is officially 10:51 a.m. right now. I have spent nearly 3 hours on organic chemistry! I hope this helps anyone who is cramming just like I am.

(If I made any mistakes, please tell me)

Sunday, October 5, 2008

The Newman Projection

Let's have some fun with organic chemistry today ^-^. Organic chemistry requires a lot of 3-D imagination, if you can see it in your head, you're basically well off!
Well, let's try a Newman Projection project! How about our friend butane (C4H10)?
"Let's look at it from that this point of view...what a beautiful molecule"

Now let's get some of the basics down before we start with the masterpiece. We need to know two kinds of formations: Staggered and Eclipsed; and also two kinds of strains: Torsional Strain and Steric Strain! (is this a foreign language lesson?)!

Here's my Staggered formation: as you can see all the atoms are not lined up, they're as far away from each other as possible. This molecule also has Steric Strain (an increase in Energy atoms are forced together) no Torsional Strains though...hmm why? let's see our next formation.


There we go, our Eclipsed formation: like the solar eclipse, get it? They're on top of each other, this stage is very high in energy because the two atoms are so close together! remember now, electrons hate each other so they want to be far away. This also has Steric Strain, but uniquely, it also has Torsional Strain: increase in Energy caused by eclipsing (electron repulsion between bonds)

So let's summarize this:

1. Staggered formation - low in energy - steric strain

2. Eclipsed formation - high in energy - steric and torsional strain.

Well, that was kind of small...but you can see the relative energy: Let me just maximize it down here!















A. Anti-staggered, steric




B. Torsional, steric



C. Gauche, steric



D. Torsional, steric




E. Gauche, steric




F. Torsional, steric


G. And the last one has the same exact
configuration as A!


R.S.V.P. Gauche configuration is basically the staggered formation while Anti-staggered is when the two large molecules (CH3 in this case) is at the opposite ends of each other.

Saturday, October 4, 2008

The Butterfly

Whenever I feel discouraged about life and wanted to find the easy way out, I realized that I have just wasted another moment of my life. Every time we sit there and try to figure out how to complete tasks the easy way, we just wasted time sitting there thinking while we could have just stood up and do something. In a way, the harder the task, the more personal satisfaction accumulates and the higher our self-esteem rises. I took this story from http://www.indianchild.com.

BUTTERFLY

A man found a cocoon of a butterfly. One day a small opening appeared. He sat and watched the butterfly for several hours as it struggled to force its body through that little hole.Then it seemed to stop making any progress. It appeared as if it had gotten as far as it could, and it could go no further.

So the man decided to help the butterfly. He took a pair of scissors and snipped off the remaining bit of the cocoon.

The butterfly then emerged easily. But it had a swollen body and small, shriveled wings.

The man continued to watch the butterfly because he expected that, at any moment, the wings would enlarge and expand to be able to support the body, which would contract in time.

Neither happened! In fact, the butterfly spent the rest of its life crawling around with a swollen body and shriveled wings. It never was able to fly.

Clearly, this kind action became an unintentional disadvantage to the butterfly. The man wanted to help ease the effort for the metamorphosis of the butterfly, but instead, had caused an impaired growth in the formation of the butterfly. The act of struggling to emerge from a cocoon is nature's testament to allow the fluid from the butterfly's abdomen to be released into the veins inside its wings. That way the wings would be fully developed according to butterflyschool.org.

In life, we encounter hardship and obstacles that might seem to be hard to overcome. However, without these hardships and obstacles, we would not be fully developed physically and mentally. Whether it is a tragic pain, a devastating situation, or a stressful environment, in the end, the experience will allow us to come out stronger than we have entered. It's all in how we cope with the situation.

Don't let others pave the way for you and just follow, you won't be be prepared enough to make it out with a newborn strength. It's just like trying to obtain good grades in school or being promoted at work, you can cheat your way through it, but in the end, you will not gain the experience and the necessary requirements to get through everything afterwards. Guide your own path, hammer and forge it into the way you want it to be, build your own monument. You can ask for help, by all means, do ask for help, but realize what kind of help would be beneficial. There will be people who would be nice enough just to give you all the answers and lay down the foundation so that you will get the result, however, that is the worse kind of help out there you can find. If everything is already laid out for you, then what is the point of working toward your goal? Is it really your own success or is it the success of another? Build your own monument and have someone build it with you instead of having someone build it for you.


Fight toward your goal! Only those who succeeds are motivated enough to continue to dream big. If Archimedes thought it was impossible to determine if the king's crown was made out of real gold or not, then there would be no law stating that the weight of the crown divided by the volume of water is equal to the density of the material.Eureka!

Friday, October 3, 2008

A Sharp Christmas Present

Start Planning for Christmas!

The Merry season is once again drawing near! Have you started your Christmas shopping yet? In two more months, you will be running all over the stores looking for a pair of shoes, the new and latest toys available, or maybe even that new WII that your child had been begging for since December 8, 2006. So you know what to get for certain people, but how about those who refuse to tell you what they want? The common phrase seems to come up, "Oh, I don't need anything," every Christmas creating an irony that suppose to make things easier, but in reality, it just makes everything worse.

How much do you spend each year on Christmas? I would assume that the combination of all the gifts for your friends and family would mount up to $1,000 or more. Why not get something that costs less than $1,000 and still applicable to everyone!! Why not get something the whole family can use?

I would suggest a set of CUTCO knives. Here are the advantages:


1. No receipt hassle, so if they want to return it you get your full money back guaranteed.

2. Personal engravings of their name on the handle.

3. Perfect for anyone who works and eat.

4. No gender preferences (works great for both male and female!)

4. Practical daily uses. (Unlike those other gifts that would get lost in who knows where and never shows up again until a decade later)

5. Buy one set and give each person a knife individually (save time from going store to store wasting gas and looking for a nice present).

6. FOREVER GUARANTEE!! Meaning the family can pass it on from generations to generations to generations and still get the same guarantee!

7. Don't like knives? There are also garden tool sets, sporting sets, flatware sets and cookware sets.


Get it before November 1st, 2008, and you can get 20% off!!! Buy any set over $700 and receive TWO FREE item of your choice!

One thing unique about CUTCO is that the product is not available anywhere in stores or officially online. The only way to get CUTCO is through Vector representatives. Wouldn't you want to know more about a product before buying it? Those products at the stores, you don't know its real value until you actually buy it. With the CUTCO knives, the representatives will spend approximately 30-45 minutes informing of the customer of the quality of the product, the credibility of the company and the guarantee that stands behind it. After the demonstration, the decision is up to you. Act now and get your CUTCO knives for 20% off before November 1st, 2008!!!

Your money is not only going to be a gift for your friends and family, it will also benefit those who are in need. The money will be to support the American Heart Association, The Salvation Army, the National Rebuilding Together Program, Children's Wish Foundation of Canada, March of Dimes, Meals on Wheels, YMCA, United Ways, Olean General Hopital, and the American Cancer Society.

Ready to make a difference and also save yourself from the hassle of searching for gifts? Contact me at xxlildreamerx0x@yahoo.com, and we can make an appointment for a presentation. Only 30 minutes of your life that can have an impact on hundreds of individuals. Make this Christmas one of your most influential Christmas possible!!!

E-mail: xxlildreamerx0x@yahoo.com (That's a zero by the way)

Merry Early Christmas!!!

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