Functional Groups By Dr. Christophy

Functional Groups “Arrangements of atoms in an organic compound that is capable of characteristic chemical reactions.” Functional groups contain at least one atom that is not C or H, usually O or N or a halogen. R is used to represent a carbon/hydrogen chain. R’ is used to represent a chain that may be different on the same molecule.

Alkyl Halides Hydrocarbon in which a halogen is attached to a carbon chain. The halogen is named as a substituent group, just like ethyl or methyl. The halogen names are fluoro-, chloro-, bromo- and iodo-

Naming Examples – Alkyl Halides Name this structure: Name this structure: Click here to see the answer Click here to see the answer

Alcohols An alcohol contains an “OH” group attached to a hydrocarbon.

Alcohols (cont.) Alcohols all have the ending “-ol”. A number indicates to which carbon the functional group is attached. The alcohol gets the lowest number possible. Example: 2-propanol

Naming Examples - Alcohols Name this alcohol Name this alcohol: Click here to see the answer Click here to see the answer

Types of Alcohols If the alcohol is attached to a carbon that is also attached to two hydrogens and one other carbon, that is a primary alcohol. If the alcohol is attached to a carbon that is also attached to one hydrogen and two other carbons, that is a secondary alcohol. If the alcohol is attached to a carbon that is also attached to no hydrogens just three other carbons, that is a tertiary alcohol.

Types of Alcohols (cont.) Identify the following as primary, secondary and tertiary alcohols: Click for the answer

Ethers When the hydrogen in an alcohol is instead replaced by a hydrocarbon group, the result is an ether: The R groups may be the same or different

Naming Ethers Ethers are named by naming the hydrocarbon on either side of the oxygen. The R-group names are placed in alphabetical order. If the R-groups are the same, the prefix “di” is used. The last word in the name is “Ether”

Naming Examples: Ether Click here to see the name Click here to see the name

Ketones A ketone, like an alcohol, has a carbon attached to an oxygen. This time, however, the C and the O are connected by a double-bond. The C=O group is called a “carbonyl” group

Naming Ketones The suffix for a ketone is “-one” Ketones are named the same way as any other hydrocarbon, except the longest chain must contain the C=O group, and the final “e” on the end of the name is replaced by “-one” Number the carbon that contains the double-bonded “O” with the lowest number possible.

Naming Examples - Ketones Click here to see the name Click here to see the name

Aldehydes Aldehydes are ketones at the end of a chain. The ending for an aldehyde is “-al” Since the carbonyl group is always at the end, there is no need for a number.

Naming Examples Click here to see the name Click here to see the name

Carboxylic Acids Carboxylic Acids are kind of a combination of an aldehyde and an alcohol.

Naming Carboxylic Acids The ending is always “-oic acid” Again, no number is needed because the group is always at the end.

Carboxylic Acid Examples Click here to see the name Click here to see the name

Esters Esters are a combination of a ketone and an ether The general formula is:

Naming An Ester Esters are just a little tricky to name. The name of the group AFTER the “O” is first. The second word in the name is the part that includes the carboxyl group and ends with “oate”

Naming Examples - Ester Click here to see name Click here to see name

Amines Amines contain a nitrogen attached to a carbon and one or more hydrogens Like alcohols, amines can be primary, secondary or tertiary. Any of these R groups could be a hydrogen

Amides An amide is attached to a carbon that has a carbonyl group.