ethyl alcohol

methane

propane

glucose

sucrose

isopropyl alcohol

acetone

formaldehyde

freon

ether testosterone

estrogen

cellulose

starch

hemoglobin

collagen

PVC

polyethlyene

polypropylene

nylonkevlar

chlorophyll

acryllic

insulin

butane

octane

paraffin

aspartame

bakalite

MSG

ascorbic acid

folic acid

urea

acetic acid

citric acid

pyruvic acid

adeninecytosine

guaninethymine

uracil

aspirin

acetaminophen

naproxenreverse transcriptasesalivary amylase

pepsinlactose

lactase

keratinelastin

stearic acid

sodium stearate

ethyl alcohol

methane

propane

glucose

sucrose

isopropyl alcohol

acetone

formaldehyde

freon

ether testosterone

estrogen

cellulose

starch

hemoglobin

collagen

PVC

polyethlyene

polypropylene

nylonkevlar

chlorophyll

acryllic

insulin

butane

octane

paraffin

aspartame

bakalite

MSG

ascorbic acid

folic acid

urea

aceitc acid

citric acid

pyruvic acid

adeninecytosine

guaninethymine

uracil

aspirin

acetaminophen

naproxenreverse transcriptasesalivary amylase

pepsinlactose

lactase

keratinelastin

stearic acid

sodium stearate

Init: 6/2/2010 by Daniel R. Barnes

WARNING: Various graphical elements in this presentation may have been taken from the world wide web without the permission of their copyright owners. Do not copy or distribute this presentation. Its very existence may be illegal.

WARNING: The teacher who made this presentation frequently uses Wikipedia as an information source. Proceed with caution.

Life as we know it is “carbon-based”.

The more you study biology, the more you begin to get the suspicion that

Okay, so that might be overstating the case a bit, but life processes sure are full of chemical reactions.

Biological structures are made of molecules, too, so organic chemistry is the basis of both the structure and function of life.

What kinds of molecules make life possible?

glucose

stearic acidDNA

hexokinase

(sugar = fuel & building materials)

(part of fat = fuel/insulation)

(genes)

(an enzyme)

CCarbon

12.01

6

http://www.youtube.com/watch?v=nqDHwd9rG0shttp://www.youtube.com/watch?v=7siZ0ON0b8I&feature=fvst

At first, chemists thought that only living things could make carbon compounds.

“Organic chemistry” these days means “the chemistry of carbon compounds”, but the word “organic” does not literally mean “having carbon”. “Organic” means “coming from or having to do with living things”.

It is true that the bodies of living things carry out many complex chemical reactions that produce lots of fancy carbon compounds.

However, one day, some guy made a chemical in his laboratory from totally nonliving materials . . .

The Wohler synthesis of urea.Friedrich Wöhler (31 July 1800 –

23 September 1882)

1828

Ammonium cyanate decomposes to ammonia and cyanic acid which in turn react to form urea in a nucleophilic

addition followed by tautomeric isomerization:

The Wohler synthesis of urea.Friedrich Wöhler (31 July 1800 –

23 September 1882)

1828

Thanks to this guy, the word “organic chemical” no longer means “chemical produced naturally by the body of a living thing”.

That’s all nice, but why are we studying organic chemistry?

SWBAT . . . relate organic chemical diversity to carbon’s bonding habits.

CCarbon

12.01

6 Why carbon? Why should carbon be the basis of the chemistry of life?

“valence electrons”

C

C

H

H

HH

C

H

H

HH

C

H

H

HH

methane

H is from group1A so it has 1 dot so it forms 1 bond

O is from group 6A so it has 6 dots so it forms 2 bonds

N is from group 5A so it has 5 dots so it forms 3 bonds

C is from group 4A so it has 4 dots so it forms 4 bonds

C

H

H

HHCNOPSFClBrI

C

H

H

CHCNOPSFClBrI

C

H

H

NHCNOPSFClBrI

C

H

H

OHCNOPSFClBrI

et cetera . . .

H 1 bond

O 2 bonds

N 3 bonds

C 4 bonds

101 = 10 possibilities

102 = 100 possibilities

103 = 1000 possibilities

104 = 10,000 possibilities

*This table is based on VERY ROUGH approximations of compound diversity potential

Of course, carbon compounds aren’t limited to having only one carbon atom in them . . .

Carbon atoms can form structures ranging from the small to the large,and from the simple to the complex.

There seems to be no limit to the length of the carbon “backbone”

C

This is a molecule of “icosane”, C20H42.

It’s not the longest possible hydrocarbon.In fact this is the shortest of the hydrocarbons used to make petroleum-based candle wax.

It’s long enough, though, that the chemist who made this picture made an “skeletal formula” to represent the molecule.

In a skeletal formula, there is an “implicit” carbon atom at the end of every line, unless another letter is already written there.

Also, each carbon will have as many unwritten hydrogen atoms bonded to it as it can hold onto with its remaining “free hands”.

H

H H

CC

CC

CC

CC

CC

CC

CC

CC

CC

C

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H H

H

This is a molecule of “icosane”, C20H42.

It’s not the longest possible hydrocarbon.In fact this is the shortest of the hydrocarbons used to make petroleum-based candle wax.

It’s long enough, though, that the chemist who made this picture made an “skeletal formula” to represent the molecule.

In a skeletal formula, there is an “implicit” carbon atom at the end of every line, unless another letter is already written there.

Also, each carbon will have as many unwritten hydrogen atoms bonded to it as it can hold onto with its remaining “free hands”.

Since a nitrogen atom can form three covalent bonds, it is possible to form a chain out of nitrogen atoms.

If a nitrogen atom is holding onto its two next-door neighbors with two of its bonds, it even has one bond left to hold onto a third atom, increasing the potential for molecular diversity.

It turns out, though, that nitrogen chains are highly explosive. They’re just not stable enough to be the basis of molecules in a living thing.

It seems that nitrogen atoms would much rather form little N2

molecules than form large molecules.

N N N N N N N NH

H

H

H

H H H

H H H

Cl

F

Br

O

Si

B OO M!Living things that explode tend

to become dead things.

N N N N N N N N N N

Sorry, nitrogen.You don’t get the job.

You can’t form stable chains.

You only make three bonds.

Carbon, you’re hired.

Your chains and polymers are stable at earthly temperatures.

You can make FOUR bonds.

Life on Earth will be based on you. Congratulations.

Hydrocarbon molecules can also have branching structures.

normal octane (no branching)

isooctane

Hydrocarbon molecules can also have branching structures.

That name is too complicated.Can we just call it “Trixie” instead?

Carbon can also form rings.

Benzene

Cholesterol

Carbon can make multi-ringed structures, too.

Testosterone

Carbon can make multi-ringed structures, too.

caffeine

Carbon can make multi-ringed structures, too.

serotonin

Carbon can make multi-ringed structures, too.

LSD

Carbon can make multi-ringed structures, too.

Carbon can also form bizarre molecules called “fullerenes”.

This particular one, whose formula is C60, is called a “buckyball”.

Boy, carbon sure can make some wacky structures thanks to its quadruple bonding capabilities! Zowie!

But there’s more . . .

Please note carbon’s position on the periodic table.

Carbon is in group 4A

A carbon atom has 4 valence electrons

Carbon needs 4 more valence electrons to have an “octet” of 8

A carbon atom likes to make 4 covalent bonds.

CA carbon atom can make 4 single bonds, or it can make a combination of single, double, and triple bonds, as long as the total number of bonds is 4.

Double vs. single bondingresults in yet another source of organic chemical diversity . . .

. . . the issue of . . .

C C

C C

C CH

H

H

H

H

H

How many dots does each carbon atom have now?

How many dots does each carbon

want to have?

How many more dots does each

carbon atom need?

How is a carbon atom most likely

to get those needed valence

electrons?

C CH

H

H

H

H

H

Let’s make some covalent bonds so our carbons can

get their octets and be happy.

C CH

H

H

H

H

H

Let’s make some covalent bonds so our carbons can

get their octets and be happy.

HH

HCCH

H

H

This is the Lewis structure for ethane, C2H6.

How many valence electrons does

each carbon atom have now?

Covalently bonding with four other atoms gave each carbon atom a nice, full octet.

Let’s make some covalent bonds so our carbons can

get their octets and be happy.

CH

CH

HH

HH

This molecule is said to be “saturated” because it contains the maximum possible amount of hydrogen.

It is also possible for hydrocarbons to be “unsaturated”. Such molecules have less hydrogen than they could.

H H

C HH

CHH

This molecule is said to be “unsaturated” because it contains less than the maximum possible amount of hydrogen.

When the two hydrogen atoms left, they took their electrons with them, so now the C’s don’t have octets anymore.

HH C C H

HThis molecule is said to be “unsaturated” because it contains less than the maximum possible amount of hydrogen.

When the two hydrogen atoms left, they took their electrons with them, so now the C’s don’t have octets anymore.

HH C C H

HThe unpaired valence electrons that used to be paried with the electrons from the missing hydrogens have now paired with each other.

A double bond has formed between the two carbon atoms.

H HH C C H

You can make an organic molecule even more unsatured by removing even more hydrogen.

H H

H C C H

You can make an organic molecule even more unsatured by removing even more hydrogen.

As before, the unpaired electrons pair with each other to form another bond. The double bond becomes a triple bond.

H C C H

You can make an organic molecule even more unsatured by removing even more hydrogen.

As before, the unpaired electrons pair with each other to form another bond. The double bond becomes a triple bond.

C

C

H

H

H

H

H

H

C

C

H

H H

HC

C

H

H

ethane

ethene

ethyne

Below is the skeletal formula of stearic acid, a “fatty acid”.

There are no carbon-carbon double bonds in this molecule’s backbone, so it is “saturated”.

Because of the regular zig-zag pattern in the molecule, it is, overall, fairly straight. Stearic acid molecules stick together easily because of this.

Even in nonpolar molecules like fatty acids, weak intermolecular attractions called “London forces” become powerful enough to cause solidification when long, straight molecules snuggle up next to each other.

Like other saturated fats, stearic acid solidifies relatively easily, so it is more likely to form artery-clogging atherosclerotic plaques that can cause heart attacks and strokes.

Oleic acid has one carbon-carbon double bond, so it is considered to be “monounsaturated”.

What’s this?

Below is the skeletal formula of oleic acid, another “fatty acid”.

The double bond in oleic acid makes the molecule bent. Therefore, it is harder for it to solidify, so it’s less likely to cause atherosclerotic plaque.

Saturation of fatty acids by nickel-catalyzed “hydrogenation”

can turn liquid oils into solid margarine.

+ H2

Ni

And now, a little review . . .

1. A carbon atom typically makes four covalent bonds[click me]

2. Carbon can form small molecules, or it can form long chains.

3. The carbon “backbone” of an organic molecule can be single-stranded or branched.

[click me]

[click me]

4. Carbon can form covalent bonds with lots of nonmetal elements such as hydrogen, oxygen, nitrogen, sulfur, and all the halogens.

[click me] [click me]

[click me][click me]

[click me] [click me]

[click me]

[click me]

5. A carbon atom can form single, double, or even triple bonds.[click me]

[click me] [click me]

[remove all rectangles]

6. Double bonds have different bonding angles than single bonds, so saturated and unsaturated compounds have different fluidities.

[click me] [click me]

[click me] [click me]

1. A carbon atom typically makes four covalent bonds

2. Carbon can form small molecules, or it can form long chains.

3. The carbon “backbone” of an organic molecule can be single-stranded or branched.

4. Carbon can form covalent bonds with lots of nonmetal elements such as hydrogen, oxygen, nitrogen, sulfur, and all the halogens.

5. A carbon atom can form single, double, or even triple bonds.

6. Double bonds have different bonding angles than single bonds, so saturated and unsaturated compounds have different fluidities.

Great. Carbon is super duper!

Now, make sure you learn the basics about polymers, especially proteins, complex

carbohydrates, and nucleic acids.

Bye-bye now! All that follows is construction site trash.

C

H

C

C C C C