Chapter 9 Organic Chemistry John Singer, Jackson Community College Chemistry for Changing Times, Thirteenth Edition Lecture Outlines © 2013 Pearson Education, Inc.

2 Chapter 9 © 2013 Pearson Education, Inc. Organic Chemistry Organic chemistry is defined as the chemistry of hydrocarbons and their derivatives. Of tens of millions of known chemical compounds, over 95% are compounds of carbon.

3 Chapter 9 © 2013 Pearson Education, Inc. The Unique Carbon Atom Carbon is unique in that carbon atoms can bond to each other to form long chains and rings.

4 Chapter 9 © 2013 Pearson Education, Inc. Hydrocarbons Hydrocarbons are the simplest organic compounds. As their name implies, they are composed entirely of carbon and hydrogen.

5 Chapter 9 © 2013 Pearson Education, Inc. Alkanes Alkanes are hydrocarbons that contain only single bonds. Because all carbon- to-carbon bonds are single bonds, alkanes are often called saturated hydrocarbons. The simplest hydrocarbon is methane (CH 4 ).

6 Chapter 9 © 2013 Pearson Education, Inc. The general formula of alkanes is C n H 2n+2. Alkanes

7 Chapter 9 © 2013 Pearson Education, Inc. The names of alkanes begin with a prefix denoting the number of carbon atoms followed by the suffix –ane. Alkanes

8 Chapter 9 © 2013 Pearson Education, Inc. Ball-and-stick and space-filling models can be used to represent organic compounds. Alkanes

9 Chapter 9 © 2013 Pearson Education, Inc. Condensed structural formulas are often used to represent organic compounds. In condensed structural formulas, C to H bond lines are omitted and the formulas are written in the following manner: propane: CH 3 CH 2 CH 3 Alkanes

10 Chapter 9 © 2013 Pearson Education, Inc. The alkanes represent a homologous series that differs by the number of –CH 2 – groups. Members of a homologous series exhibit properties that vary in a regular and predictable manner. Alkanes

11 Chapter 9 © 2013 Pearson Education, Inc. Isomerism: Isomers are compounds with the same molecular formula, but different structural formulas. Alkanes

12 Chapter 9 © 2013 Pearson Education, Inc. Alkanes

13 Chapter 9 © 2013 Pearson Education, Inc. Cyclic Hydrocarbons Cyclic hydrocarbons are ring compounds. The simplest cyclic hydrocarbon is cyclopropane.

14 Chapter 9 © 2013 Pearson Education, Inc. The names of cyclic hydrocarbons begin with the prefix cyclo- followed by the name of the alkane with the same number of carbon atoms. Cyclic Hydrocarbons

15 Chapter 9 © 2013 Pearson Education, Inc. Unsaturated Hydrocarbons Alkenes are hydrocarbons that contain a carbon-to-carbon double bond. Their general formula is C n H 2n. Their names begin with a prefix denoting the number of carbon atoms followed by the suffix –ene. Ethylene is the simplest alkene.

16 Chapter 9 © 2013 Pearson Education, Inc. Alkynes are hydrocarbons that contain a carbon-to- carbon triple bond. Their general formula is C n H 2n-2. Their names begin with a prefix denoting the number of carbon atoms followed by the suffix –yne. Ethyne (acetylene) is the simplest alkyne. Unsaturated Hydrocarbons

17 Chapter 9 © 2013 Pearson Education, Inc. Both alkenes and alkynes are unsaturated hydrocarbons. A saturated hydrocarbon has the maximum number of hydrogen atoms attached to each carbon and no double or triple bonds. Unsaturated hydrocarbons can undergo an addition reaction, such as that seen on the right here. Unsaturated Hydrocarbons

18 Chapter 9 © 2013 Pearson Education, Inc. Aromatic Hydrocarbons: Benzene and Relatives Benzene is a unique organic compound in that it is a very stable six-carbon ring. Aromatic hydrocarbons contain a benzene ring or have properties similar to those of benzene.

19 Chapter 9 © 2013 Pearson Education, Inc. Aromatic Hydrocarbons: Benzene and Relatives

20 Chapter 9 © 2013 Pearson Education, Inc. Aromatic Hydrocarbons: Benzene and Relatives

21 Chapter 9 © 2013 Pearson Education, Inc. Chlorinated Hydrocarbons When chlorine is substituted for one or more hydrogen atoms of a hydrocarbon, a chlorinated hydrocarbon is formed. Chlorinated hydrocarbons have many useful properties. Dichloromethane is used as a solvent and paint remover. Trichloromethane (chloroform) is also a solvent and at one time was used as an anesthetic. It is now considered hazardous.

22 Chapter 9 © 2013 Pearson Education, Inc. Chlorofluorocarbons Carbon compounds with both chlorine and fluorine are known as chlorofluorocarbons (CFCs).

23 Chapter 9 © 2013 Pearson Education, Inc. Functional Groups Functional groups are atoms or groups of atoms that are attached to, or part of, the hydrocarbon skeletons and give the compounds characteristic chemical and physical properties. Double and triple bonds, as well as halogen substituents, are examples of functional groups.

24 Chapter 9 © 2013 Pearson Education, Inc. Functional Groups

25 Chapter 9 © 2013 Pearson Education, Inc. Alkyl Groups Alkyl groups are derived from the alkanes.

26 Chapter 9 © 2013 Pearson Education, Inc. Alcohols Alcohols contain the hydroxyl (-OH) functional group. Examples include: MethanolCH 3 OH EthanolCH 3 CH 2 OH 1-propanolCH 3 CH 2 CH 2 OH

27 Chapter 9 © 2013 Pearson Education, Inc. Methanol Methanol or methyl alcohol is sometimes called wood alcohol. It is an important solvent, automotive fuel additive, and possible fuel replacement.

28 Chapter 9 © 2013 Pearson Education, Inc. Ethanol Ethanol or ethyl alcohol is also known as grain alcohol. It is the alcohol of alcoholic beverages. It is also an additive to automotive fuel and is being considered as a gasoline replacement.

29 Chapter 9 © 2013 Pearson Education, Inc. Toxicity of Alcohols All alcohols are toxic. Methanol, for instance, is oxidized to formaldehyde by liver enzymes. Formaldehyde is a poison and can cause blindness or death. Even ethanol is toxic. The effects of drinking ethanol are due to its toxicity. Drunk driving, alcoholism, and fetal alcohol syndrome are all effects due to the toxicity of ethanol.

30 Chapter 9 © 2013 Pearson Education, Inc. Ethanol

31 Chapter 9 © 2013 Pearson Education, Inc. Multifunctional Alcohols Some alcohols contain more than one hydroxyl group.

32 Chapter 9 © 2013 Pearson Education, Inc. Phenols Phenols are aromatic compounds with the hydroxyl group attached to the aromatic ring. The presence of the aromatic ring alters the properties of the hydroxyl group. Phenols do not act as alcohols, but as acids. Phenols are an effective antiseptic.

33 Chapter 9 © 2013 Pearson Education, Inc. Ethers Ethers are compounds with two alkyl groups bonded to the same oxygen. General formula: ROR or ROR’ CH 3 CH 2 OCH 2 CH 3 is diethyl ether.

34 Chapter 9 © 2013 Pearson Education, Inc. Ethers

35 Chapter 9 © 2013 Pearson Education, Inc. Aldehydes and Ketones Aldehydes and ketones are two families of organic compounds that contain the carbonyl (C=O) functional group.

36 Chapter 9 © 2013 Pearson Education, Inc. Aldehydes and Ketones

37 Chapter 9 © 2013 Pearson Education, Inc. Carboxylic Acids Organic acids contain the carboxyl (COOH) functional group.

38 Chapter 9 © 2013 Pearson Education, Inc. When a carboxyl group is attached directly to a benzene ring, the compound is called benzoic acid. Carboxylic Acids

39 Chapter 9 © 2013 Pearson Education, Inc. Esters Esters are formed by replacing the hydrogen of a carboxylic acid with the alkyl group of an alcohol or phenol.

40 Chapter 9 © 2013 Pearson Education, Inc. Esters generally have a pleasant odor. Esters

41 Chapter 9 © 2013 Pearson Education, Inc. Esters are named by stating the name of the alcohol part first followed by the root name of the acid. Drop the –e and add the suffix –oate. For example: Methyl butanoate Esters

42 Chapter 9 © 2013 Pearson Education, Inc. Amines and Amides Amines are derivatives of ammonia. When one or more hydrogen of ammonia is replaced by an alkyl group, an amine is the result. Like ammonia, amines tend to be basic and have similar odors.

43 Chapter 9 © 2013 Pearson Education, Inc. Aniline has an amine functional group attached to a benzene ring. Amines and Amides

44 Chapter 9 © 2013 Pearson Education, Inc. Amines and Amides

45 Chapter 9 © 2013 Pearson Education, Inc. Amides have nitrogen bonded to a carbonyl carbon. The amino acids of proteins are linked by amide linkages. Amines and Amides

46 Chapter 9 © 2013 Pearson Education, Inc. Heterocyclic Compounds Heterocyclic compounds are rings that contain atoms other than carbon as part of the ring. Most organic heterocyclic compounds contain nitrogen, oxygen, or sulfur.

47 Chapter 9 © 2013 Pearson Education, Inc. Alkaloids Alkaloids are amines that occur naturally in plants, bacteria, fungi and animals. Many have physiological effects. Morphine, caffeine, nicotine, and cocaine are alkaloids. So are the bases pyrimidine and purine.