Organic Chemistry 2
Other classes of organic compounds
Functional Groups from Alkenes to Amides
Ethene-a typical alkene
contain a carbon–carbon double bond that forms when adjacent carbon atoms share two pairs of valence electrons.
are flat because the atoms in a double bond lie in the same plane.
have a trigonal planar arrangement around the double bonded carbon atoms.
is used to accelerate the
ripening of fruits.
Alkynes
have a triple bond that forms when two carbon atoms share three pairs of valence electrons.
have a 180Ëš angle and are linear.
reacts with oxygen in a combustion reaction producing temperatures above 3300 ËšC.
is used in welding.
Alkenes and Alkynes react with hydrogen gas
Alkenes and alkynes react with hydrogen gas to form saturated hydrocarbons. In the picture above, an alkyne is reacting with hydrogen gas in the presence of a metal catalyst (depicted as a pile of metal atoms) to form an alkene.
Naming Alkenes and Alkynes
A few examples for naming
Polymers
Polymers are large, long-chain molecules found in nature, including cellulose in plants, starches in food, and proteins and DNA in the body also made synthetically, for example, polyethylene and polystyrene, Teflon, and nylon.
Polymers can be made from recycled materials
You can identify the type of polymer used to manufacture a plastic item by looking for the recycling symbol (arrows in a triangle).
Aromatic Hydrocarbons
Benzene-the quintessential aromatic compound
- benzene is written as two possible ring structures and as a hexagon with a circle drawn inside
- benzene is found in many compounds with fragrant odors; thus the family of benzene compounds are called aromatic compounds
- benzene contains six electrons in the ring shared equally between six carbon atoms
- benzene is extremely stable due to the resonance between the double bonds in the
benzene ring
Naming benzene derivatives
Aromatic compounds are named
- with benzene as the parent chain
- with the name of a substituent in front of the name benzene
- with common names for some substituted compounds (see picture below)
- When benzene has only one substituent, it is not numbered.
- When there are two or more substituents, the ring is numbered to give the substituents the lowest possible numbers.
- When a common name such as phenol is used with a second substituent, the –OH in phenol is on the number one carbon.
Alcohols, phenols, and ethers
Alcohols, phenols, and ethers
An alcohol contains a hydroxyl (–OH) group which is bonded to the hydrocarbon chain of an alkane.
A phenol contains a hydroxyl (–OH) group which is bonded to a benzene ring.
Ethers have two carbon atoms attached to the oxygen atom.
Naming Alcohols
Alcohols are named with an IUPAC name that replaces the e in alkane name with ol
as simple alcohols using the name of the alkyl group of the corresponding alkane followed by alcohol such as CH4 methane CH3─OH methanol (methyl alcohol)
Alcohols with one or two carbons do not require a number for the hydroxyl group.
CH3—CH2—OH ethanol, (ethyl alcohol)
For alcohols with three or more carbon atoms, the chain is numbered to give the
–OH group the lowest number. For example, CH3─CH2—CH2—CH2—OH
1−butanol, (butyl alcohol)
Name ethers by the alkyl groups attached to either side of the middle oxygen atom (alphabetically)
Aldehydes and Ketones
Aldehydes and ketones can be made from alcohols (but not tertiary alcohols)
Primary alcohols can be oxidized to aldehydes or ketones depending on conditions. Secondary alcohols are oxidized to ketones only
Some examples of aldehydes and ketones
Carboxylic acids and esters
Carboxylic acids
Esters
Alcohols and carboxylic acids make esters
Naming carboxylic acids and esters
Amines and amides
Amines can be primary, secondary, or tertiary depending on the number of H atoms replaced in ammonia
Aromatic amines are named as derivatives of aniline
Naming amines-examples
Alkaloids are complex biological amines
Nicotine
Is very addictive as it attaches to pleasure centers in brain much like another alkaloid-heroin.
Morphine
Codeine
Oxycontin-a synthesized prescription drug which is also an alkaloid
Amides are made from carboxylic acids and amines
Some amide examples
Extra Practice
Here are some sites for practice:
practice naming alkenes and alkynes
good resource for naming benzene derivatives and more
good site for practice of benzene derivatives
practice naming aldehydes and ketones
practice for naming carboxylic acids and their derivatives
Naming carboxylic acids-harder!
Type in naming for carboxylic acids and esters