Continuing Functional Groups: Carboxylic Acids and Ethers

Carboxylic Acids
>Carboxylic Acids are formed by the function group:

>use standard rules but change the parent chain ending to -oic acid.
>The simplest carboxylic acid is methanoic acid:

EXAMPLES

Ethers
>An ether contains a oxygen group connected to two alkyl (carbon) chains
>R-O-R (remember that “R” simply symbolizes a carbon chain of any length) 
> Name the smaller alkyl group, then the second alkyl group followed by “Ether”



Alicyclics and Aromatics

Alicyclics:
>carbon chains can form 2 types of closed loops
>alicyclics are loops usually made with single bonds
>if the parent chain is a loop, standard naming rules apply with one condition: “cyclo” is added in front of the parent chain.

There are 3 different ways to draw organic compunds:

>numbering on alicyclics can start anywhere and co clockwise or counterclockwise on the loop, but side chain numbers must be the lowest possible

>loops can also be a side chain!
>same rules apply but the side chain is given a cyclo- prefix

Aromatics:
>benzene is a common cyclic hydrocarbon with unique bonds between the carbon atoms

>structurally it can be drawn with alternating double bonds
>careful analysis shows that all 6 C-C bonds are identical and really represent a 1.5 bond.
>this is due to electron resonance
>electrons are free to move all around the ring

Aromatic Nomenclature:
>a benzene molecule is given a special diagram to show it’s unique bond structure
>benzene can be a prent chain or a side chain
>as a side chain it is given the name phenyl

Ester Lab

Today in class we made esters! Esterification is the combining of a carboxylic acid and an alcohol. We decided to make a spearmint-scented ester by combining vinegar with an alcohol in a test tube and then putting it on a hot plate for about 10 minutes. After removing it from the hot plate, we let it cool in ice water for several minutes before taking a whiff of our creation. AND WHADDAYA KNOW. Even though we were busy flapping our lab coats around like the cool students we are, our spearmint-scented ester turned out to be delightful smelling! Go us!

Olivia

The Wonderful World of Esters

Esters have a bonded O between two carbon chains as well as a double-bonded O on one of the carbon chains.

Ethyl Butanoate

Propyl Ethanoate

ESTERIFICATION


Esters are created by a reaction between a carboxylic acid and an alcohol. They also form water.

Carboxylic Acids and Ethers

Carboxylic Acids are formed by the function group:

There is a double bonded oxygen atom and a hydroxide ion bonded onto the last carbon in the chain.

  • take off the -e ending and add -oic acid
  • all other naming rules apply!

Here are some examples:

ethanoic acid

2 methyl butanoic acid

pentanoic acid

benzoic acid

Be careful with this one! The carbons in benzene can only make 1 more bond so in order to have a double bonded oxygen atom and a hydroxide ion, you have to add a carbon onto the benzene and from that one add the oxygen and hydroxide.

3 ethyl benzoic acid

Ethers contain an oxygen group connected to 2 alkyl (carbon) chains:

  • name the smaller alkyl group first then the second alkyl group 
  • end with the word “ether”

Here are some examples:

dimethyl ether

hexyl phenyl ether

diphenyl ether

olivia

Introducing Functional Groups: Alcohols and Halides

Functional Groups are organic compounds containing elements other than just C & H. There are 9 different functional groups: Alcohols, Halides, Aldehydes, Ketones, Caroxylic Acids, Ethers, Amines, Amides, and Esters.

** Carbon chains without side chains can be written simply as R-

ALCOHOLS

Alcohols are organic compounds bonded with -OH. Because there is a Hydrogen bond present in the molecule, Alcohols have a high boiling point.

Alcohols have the same nomenclature rules as other organic compounds, except an -ol is added to the end. The -OH gets the lowest number.

4 methyl 1 pentanol

1 decanol

8 methyl 1 nonanol

**phenol

HALIDES

Halides are organic compounds with Halogens (Group 7 on the periodic table) bonded to them.

The same base nomenclature rules apply, though side chains are named using floro, chloro, bromo, and iodo.

1 bromo 1 chloro butane

1, 3 dibromo 5 chloro benzene

1, 2 dibromo 2 chloro propane

Alkenes and Alkynes > Double and Triple Bonds

  • carbon can form double and triple bonds with carbon atoms
  • when multiple bonds form, fewer hydrogens are attached to the carbon atom
  • the position of the double and triple bond always has the lowest number and is put in front of the parent chain

DOUBLE BONDS (ALKENES) END IN -ENE

TRIPLE BONDS (ALKYNES) END IN -YNE

1 pentene:
 

vs.

2 pentene:

Examples:

1) Name this compound:

-identify the parent chain: 1 butene

make sure the double or triple bond is the lowest possible number

it is butene because there is a double bond

-name the side chains: 3 methyl

same naming method as alkanes

Final name: 3 methyl 1 butene

2) Draw this compound

2, 3 dimethyl 2 propene

CH3 - C   =  CH

           l         l

        CH3    CH3

TRANS AND CIS BUTENE:

  • if 2 adjacent carbons are bonded by a double bond AND have side chains on them, 2 possible compounds are possible

cis 2 butene:

trans 2 butene:

MULTIPLE DOUBLE BONDS:

  • more than 1 double bond can exist in a molecule
  • use the same multipliers inside the parent chain

3) Draw this compound

2, 4 pentadiene

CH3 - CH = CH - CH = CH2

olivia

Organic Chemistry Introduction- Naming

.Organic Chemistry is the study of Carbon compounds. Carbon forms multiple covalent bonds, found in chains, rings, and branches. There are over 17 million organic compounds, in comparison to 100,000 non-organic compounds. The simplest organic compounds are made of C and H.

A saturated compound is a compound with no double and triple bonds.

Compounds with only single bonds are called alkanes. They end in -ane.

There are three categories of organic compounds: Straight Chains, Aromatics, and Cyclic Chains.

NAMING STRAIGHT CHAINS

1) Circle the longest, continuous chain and name it the BASE.

2) Number the base chain so the side chains have the lowest possible numbers.

3) Name each side chain using its -yl ending.

4) Give each side chain the appropriate number ending before -yl.

5) List the side chains alphabetically.

EXAMPLES

The longest chain is the two C’s. This is called the base chain. Because there are two C’s in it is called ETHANE. This is the simplest Carbon compound.

The condensed structural formula for ETHANE is CH3 —- CH3.

The longest chain has 6 carbons in it. This determines that the base chain is HEXANE.  There is a side chain on the 2, 3, and 4. The side chain on 2 has one carbon in it so that side chain is called 2-methyl. The side chain on 3 has two carbons in it so it is called 3-ethyl. The side chain on 4 has one Carbon in it as well so you can combine the methyl on 2 with it, creating 2,4 dimethyl (using a multiplier in front of the term).

The full term is 3-ethyl 2,4 dimethyl hexane.