B07 Alcohols, Corboxylic Acids & Esters.notebook. November 19, Alcohols

Transcription

1 Alcohols There is more to alcohol than just beverages. In fact, most alcohols are poisonous. THis is what makes them effective as disinfectants and cleaners. 1

2 What makes an alcohol and alcohol? If a hydrocarbon has a hydroxyl functional group attached to it where there should be a Hydrogen, that changes the properties of the hydrocarbon it makes it an alcohol. 2

3 Nomenclature of Alcohols 1. Find the hydroxyl functional group on the molecule and circle it 2. Determine the parent chain of carbon atoms, starting at the end nearest the hydroxyl group 3. Use the method of naming hydrocarbons to determine the initial part of the name 4. Communicate the location of the hydroxyl group on the parent chain, and add the suffix that represents the presence of a hydroxyl group 3

4 Example Problem 2.4 Gas line antifreeze contains what is sometimes referred to as methyl alcohol or wood alcohol. Determine the systematic name of this structure. 4

5 Example Problem 2.5 Isopropyl alcohol is commonly sold in stores as a disinfectant. Use the chemical structure provided to write the systematic name for isopropyl alcohol 5

6 Example Problem 2.6 Propan 1 ol, is used as a grease remover in some cleaning products. Draw the chemical structure for propan 1 ol. 6

7 Assignment p 266#18, 19, 20 7

8 Carboxylic Acids 8

9 This type of substance is created when hydrogens of a hydrocarbon are replaced with two items... a hydroxyl group and a carbonyl group: OH =O Hydroxyl Group Carbonyl Group Usually, alcohols are converted to carboxylic acids. Because hydroxyl uses a single bond and the carbonyl uses a double, this functional group can only exist on the end of a parent chain Carbonyl Carboxyl Functional Group hydroxyl 9

10 Assignment p267 #21 10

11 Naming Carboxylic Acids 1. Name the parent chain 2. Change the ending to "oic acid" 11

12 Example Problem 2.7 Propanoic acid is used to prevent some foods from spoiling. a) Use the systematic name to draw the chemical structure for propanoic acid b) State weather it is possible to have the carboxyl functional group on the second carbon in the parent chain of propanoic acid. 12

13 Assignment p268 #22 13

14 Esters 14

15 Esters are created when an alcohol and a carboxylic acid are combined. Combining these two will always create an ester and a water molecule. The functional group for an ester has a double bonded oxygen and a single bonded oxygen When the alcohol and the carboxylic acid combine, the alcohol will lose a H from its hydroxyl group. The carboxylic acid will lose its entire hydroxyl group. This is where the two molecule will connect. 15

16 Example Problem 2.8 A chemical reaction occurs between propanol and ethanoic acid. Use a structural diagram to show the reactants and products for this reaction 16

17 Naming Esters 1. Find the ester functional group, and draw a box around it. Then circle the chain of carbon atoms that extend from the functional group. 2. Locate the chain of carbon atoms that is attached to the functional group by a single bond to an oxygen atom. 3. Identify the number of carbons in this chain 4. Count the number of carbon atoms in the chain, starting with the carbon that contains a double bond to an oxygen atom 5. Identify the number of carbons in this chain 6. List the parts identified in steps 3 and 5, followed by the suffix "oate" 17

18 Example Problem 2.9 The ester depicted here produces an aroma similar to that of raspberries. Write the systematic name for this ester. 18

19 Assignment p273 #23, 24 19

20 Polyesters Polyesters are esters with multiple functional groups. This allows for long chains to be formed 20

21 Assignment p273 #23, 24 Assignment p277 # 21