Chem 1075 Chapter 19 Organic Chemistry Lecture Outline

Transcription

1 Chem 1075 Chapter 19 Organic Chemistry Lecture Outline Slide 2 Introduction Organic chemistry is the study of and its compounds. The major sources of carbon are the fossil fuels: petroleum, natural gas, and coal. Currently, about organic compounds account for about of all known substances. Each year, over new organic compounds are synthesized. Slide 3 Hydrocarbons A hydrocarbon is a compound that contains only and. A hydrocarbon derivative is a compound derived from a hydrocarbon but containing such a fluorine, nitrogen, and oxygen. There are two types of hydrocarbons: hydrocarbons hydrocarbons Slide 4-5 Saturated and Unsaturated Hydrocarbons A saturated hydrocarbon has only bonds between the carbon atoms. Carbon can form four single covalent bonds to other atoms. A saturated hydrocarbon with only single bonds belongs to the family (a). An unsaturated hydrocarbon has either a or bond between two carbon atoms. If it has a double bond, it is an (b). If it has a triple bond, it is an (c). An aromatic hydrocarbon has a ring. A benzene ring is a 6- membered ring of carbon atoms with alternating bonds (d). Slide 6 Classification of Hydrocarbons

2 Slide 7 Alkanes Alkanes are a family of compounds whose names end in the suffix. They are hydrocarbons. They each have the same general molecular formula:. The fifth member of the alkane family, pentane, has 5 carbon atoms and ( = 12) hydrogen atoms,. Slide 8 Alkane Family

3 The lighter alkanes ( carbons) are used as fuels while the larger alkanes ( carbons) are solids used to make waxes and candles. Slide 9 Structural Isomers Two compounds with the molecular formula but structural formulas are. Butane has the formula. We can draw the formula in two ways: The two isomers have physical properties. Slide 10 Alkyl and Aryl Groups When a hydrogen is removed from an alkane, an results. methane methyl group ethane ethyl group When we remove the hydrogen atom, the name suffix is changed to Slide 11 Alkyl and Aryl Groups

4 Slide 12 Guidelines for Naming Alkanes 1. Name an alkane for its carbon chain regardless of the branches. 2. Number the longest continuous chain starting from the end to the on the chain. 3. Indicate the position of the alkyl groups by and. 4. If there are two or more of the same group attached to the chain, use the prefixes, etc. Slide Nomenclature of Alkanes What is the name of the following alkane? CH 3 CH 3 CH 2 CH 2 CH 2 CH CH 3 What is the name of the following alkane? CH 3 CH 3 CH 2 CH CH CH 3 CH 3 Slide 15 Alkane Reactions The C-C and C-H bonds in alkanes are very strong and unreactive at room temperature. At high temperatures, alkanes burn rapidly in the presence of. This is a. The products of a combustion reaction are and. Slide 16 Alkene & Alkyne Formulas Alkenes contain one or more double bonds. The general molecular formula for an alkene with one double bond is C n H 2n. Alkynes contain one or more triple bonds. The general molecular formula for an alkyne with one triple bond is C n H 2n-2.

5 Slide 17 Alkene Family Butene, C 4 H 8, has two. The double bond can be between the first and second carbon or between the second and third carbon. Slide 18 Guidelines for Naming Alkenes 1. Name an alkene for its chain that the. The name is the same as the alkane with the -ane suffix changed to. 2. Number the longest continuous chain starting from the end to the. 3. Indicate the position of the attached alkyl groups by name and number. 4. If there are two or more of the same group attached to the chain, use the prefixes di-, tri-, tetra-, etc. Slide 19 Nomenclature of Alkenes What is the name of the following alkene? CH 2 CH 3 CH 3 CH 2 CH 2 C=CH 2 Slide 20 Alkyne Family Butyne, C 4 H 6, has two. The triple bond can be between the first and second carbon or between the second and third carbon.

6 Slide 21 Guidelines for Naming Alkynes 1. Name an alkene for its chain that the bond. The name is the same as the alkane with the -ane suffix changed to. 2. Number the longest continuous chain starting from the end to the bond. 3. Indicate the position of the attached alkyl groups by and. 4. If there are two or more of the same group attached to the chain, use the prefixes di-, tri-, tetra-, etc. Slide 22 Nomenclature of Alkynes What is the name of the following alkyne? CH 3 HC C CH CH 3 Slide 23 Reactions of Alkenes & Alkynes In addition to combustion reactions, alkenes and alkynes also undergo. The double or triple bond can add atoms. There are two types: hydrogenation and halogenation. Hydrogenation Halogenation Slide 24 Polymerization Reactions A polymer is a giant molecule made up from many small molecules ( ) joined in a long chain. Ethylene, CH 2 =CH 2, can react to give. We represent the polymer as [-CH 2 -CH 2 -] n. monomer polymer

7 Slide 25 Arenes Arenes contain a ring. Arenes are also called compounds because of their fragrant smell. The formula for benzene is and it has a structure. The double bonds are and benzene is often written with a in the middle. Slide Isomers of Disubstituted Benzene If we replace two of the hydrogens on benzene with chlorines, we have, C 6 H 4 Cl 2. The chlorine atoms can be arranged in different ways: If the chlorines are on carbons, we have or. If the chlorines are separated by, we have or. If the chlorines are each other, we have or. Slide 28 Hydrocarbon Derivatives There are millions of organic compounds. We can categorize them into classes of compounds. Each of the classes has a specific. A functional group is a set of atoms that gives a class of compounds its characteristics. There are 10 classes: five a carbonyl group and five a carbonyl group (C=O). Slide 29 Non-Carbonyl Classes of Hydrocarbon Derivatives Here are the basic hydrocarbon classes. R is an alkyl group and Ar is an aryl group.

8 Slide 30 Carbonyl Classes of Hydrocarbon Derivatives Slide 31 Organic Halides If a halogen atom (_X= ) replaces a hydrogen atom in a hydrocarbon, the new compound is an Organic halides are used primarily as household and industrial. They are found in many. They are essentially nonpolar molecules with low boiling points and properties similar to those of alkanes. Slide 32 Alcohols and Phenols When an group replaces a hydrogen atom on an, the result is an.

9 When an replaces a hydrogen atom on an, the resulting molecule is a. The OH group is called a. The name of alcohols is derived from the parent alkane by changing the -ane ending to an suffix. For example, is ethanol Slide 33 Alcohols and Phenols Continued Most alcohols are quite because of the OH group which allows for. Alcohols higher boiling points are different than their parent alkanes. Slide 34 Ethers Organic molecules with two hydrocarbon groups attached to an are, R-O-R. Ethers are usually named by indicating the to the oxygen. Ethers hydrogen bond and their properties lie between those of alkanes and alcohols. Slide 35 Amines If an alkyl or aryl group replaces a hydrogen in ammonia, an results, R-NH 2. Amines are often referred to by their, indicating the alkyl group present. Most amines are due to their ability to hydrogen bond.

10 Slide 36 Aldehydes contain a carbonyl (C=O) group and are. In an aldehyde, the carbonyl group is attached to a and an alkyl or aryl group,. The name of an aldehyde is derived from its parent alkane by changing the -ane to an suffix. Slide 37 Ketones also contain the carbonyl group and are generally polar. Ketones have attached to the carbonyl group. Ketones are named for their parent alkane and end in suffix. Slide Carboxylic Acids In a carboxylic acid, a group and alkyl or aryl group is bonded to a group,. This group, -COOH, is a.

11 Acetic acid,, is a major component of vinegar and gives it its sour taste. Carboxylic acids are named from their parent alkane by dropping the -ane ending and replacing it with a suffix. Carboxylic acids are since the carboxyl group, COOH, can form. They have similar properties to alcohols with boiling points and water solubility. Slide 40 Esters An ester has an R and an OR group bonded to a carbonyl group, RCOOR. Esters typically have a. They are slightly polar. They are typically formed from the reaction of an with a. Slide 41 Amides In amides, a group is attached to an alkyl or aryl group and an group. Amides are formed from the reaction of a with. They are polar molecules with properties similar to those of carboxylic acids.

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