1. Chapter 21.1 and 2 Functional Groups and Classes of Organic Compounds

2. Define “functional group” and explain why functional groups are important. Identify and alcohols, alkyl halides, ethers, aldehydes, ketones, carboxylic acids, esters, and amines based on the functional group present in each Explain the relationships between the properties and structures of compounds with various functional groups Objectives:

3. Functional Groups An atom or group of atoms that is responsible for the specific properties of an organic compound Compounds that contain the same functional group can be classed together Makes properties that are very different from those of the corresponding hydrocarbon.

4. Comparing Classes of Organic Compounds

5. Common Functional Groups

6. More Functional Groups

7. Alcohols Organic compounds that contain one or more hydroxyl groups General formula for a class of organic compounds Consists of the functional group and the letter R which stands for the rest of the molecule General formula for alcohols R–OH Hydroxyl group, –OH, Makes alcohols able to hydrogen-bond makes them soluble in water

8. Uses of Alcohols Lotions, creams, and cosmetics usually contain an alcohol called glycerol to keep them moist Alternative fuels Ex: gasohol, a one-to-nine ratio of ethanol and gasoline Simple alcohols - Ethanol Poisonous to some extent

9. Alkyl Halides Organic compounds in which one or more halogen atoms—fluorine, chlorine, bromine, or iodine— are substituted for one or more hydrogen atoms in a hydrocarbon General formula of an alkyl halideis R–X (where X represents any halogen). EX: Chlorofluorocarbons, or CFCs (implicated in ozone-layer depletion) Teflon®, a polymer made from tetrafluoroethene, C2F4

10. Ethers organic compounds in which two hydrocarbon groups are bonded to the same atom of oxygen General formula of an ether: R–O–R’ R’ represents a hydrocarbon group R same or different hydrocarbon group Not very reactive compounds Relatively nonpolar Uses: Solvents Some have pleasant odors, used in perfumes

11. Alcohol Nomenclature Name Parent hydrocarbon: Longest chain containing hydroxyl group Drop –e, add –ol More than one hydroxyl group 2 -diol 3 -triol Number so hydroxyl group has lowest number possible Insert number immediately before name of parent hydrocarbon OH OH C C C C C C C C 1-butanol 2,2 - butandiol OH

12. Alkyl Halide Nomenclature Name Parent hydrocarbon Find longest chain Prefixes for halogens --- fluoro, bromo, chloro , iodo If more than one, put in alphabetical order If more than one of the same, use prefixes di, tri, tetra Number carbon atoms Lowest number in it’s name If halogen in same position – alphabetical Br Br Cl Cl Cl C C C C C C C C 1,2 - dibromobutane Cl 1,1,1,3 - tetrachlorobutane

13. Ether Nomenclature Name the parent compound The word ether will come at the end of the name Add names of alkyl groups Arrange names in alphabetical order If both are same, use prefix –di Leave spaces in the name Space between alkyl group names and ether C O C C C C C O C C C diethyl ether ethyl propyl ether

14. Contain the carbonyl group. Aldehydes organic compounds in which the carbonyl group is attached to a carbon atom at the end of a carbon-carbon chain Ketones organic compounds in which the carbonyl group is attached to carbon atoms within the chain Aldehydes and Ketones

15. The general formula for an aldehyde is: The general formula for a ketone is: Aldehydes and ketones are often responsible for certain odors and flavors

16. Locate parent compound Longest chain containing carbonyl group Always number carbonyl group as 1 Change –e to –al All other rules apply (ex: number from side closest to the carbonyl group Aldehyde Nomenclature C O C O C O C C C C C C C C C C C C C propanal 3,3 - dimethylpropanal 2 – ethyl pentanal

17. Locate Parent compound Must contain carbonyl group and it must contain the lowest number Change –e to –one All other rules apply Ketone Nomenclature O O C O C C C C C C C C C C C C C propanone 2 - pentanone C 2,2 - dimethyl – 3 - pentanone

18. Amines Amines Organic compounds that can be considered to be derivatives of ammonia, NH3 General formula of an amine : Amines are common in nature. Often form during the breakdown of proteins in animal cells The unshared electron pair on the nitrogen makes amines act as weak bases in aqueous solutions:

19. Amine Nomenclature Name the parent compound End will be –amine Add alkyl groups Alphabetical order Use prefixes, di-, tri- H H C C H N C C N C C C N methylamine ethylmethylamine trimethylamine PRIMARY AMINE SECONDARY AMINE TERTIARY AMINE

20. Carboxylic Acids organic compounds that contain the carboxyl functional group General formula: Like inorganic acids Carboxylic acids react to lose a hydrogen ion and become a negatively charged ion in water

21. Examples acetic acid (the weak acid in vinegar) citric acid benzoic, propanoic, and sorbic acids (used as preservatives) Much weaker than many inorganic acids

22. Carboxylic Acids Found in Plants and Animals

23. Carboxylic Acid Nomenclature Name Parent Compound Longest chain contains carboxyl group Drop –e, add –oic acid More than one, use full name of parent compound (don’t drop -e ) -dioic acid = 2, -trioc acid = 3 O O O O C C C OH C C OH C C C OH C HO propanoic acid C ethanedioic acid 3 - methylbutanoic acid

24. Esters organic compounds that have carboxylic acid groups in which the hydrogen of the hydroxyl group has been replaced by an alkyl group General formula: considered derivatives of carboxylic acids because of their structural similarity to carboxylic acids Like aldehydes and ketones, esters are responsible for many common odors and flavors

25. Common Odors and Flavors of Esters

26. Esters Nomenclature Name parent compound Name carboxylic acid Change –oic acid to –oate Add the name of the alkyl group This will be the front of the name O O C O C C C C C O C C C C Methyl butanoate ethyl propanoate