Download presentation
Presentation is loading. Please wait.
1
Carboxylic Acids
2
Carboxylic Acids A carboxylic acid contains a a hydroxyl group (–OH) attached to a carboxyl group, which is a carbonyl group . © 2013 Pearson, Education Inc.
3
IUPAC Names of Carboxylic Acids
4
IUPAC Names of Carboxylic Acids
Use the same IUPAC rules and add… The carboxylic acid group needs to be included in the longest chain of carbons. The carbon of the carboxylic acid group is given the number 1 (since it is on the end of a chain) The suffix becomes anoic acid.
5
IUPAC Names of aromatic Carboxylic Acids
The name of the carboxylic acid of benzene, is benzoic acid. The carbon in the carbonyl group is bonded to carbon 1 in the benzene ring. The ring is numbered to give the lowest possible numbers for any substituents. The prefixes ortho, meta, and para may be used to show the position of one other substituent.
6
IUPAC Names of Carboxylic Acids
The prefixes ortho, meta, and para may be used to show the position of one other substituent. Insert diagram of benzoic acid, 4-aminobenzoic acid and 3,4-dichlorobenzoic acid bottom pg 571 with labels.
7
Common Names of Carboxylic Acids
Many carboxylic acids are still named by their common names that include prefixes, form, acet, propion, butyr. When using the common names, the Greek letters alpha (), beta (), and gamma () are assigned to the carbons adjacent to the carboxyl carbon.
8
Formic Acid A red ant sting contains formic acid that irritates the skin.
9
Guide to Naming Carboxylic Acids
10
IUPAC Names for Carboxylic Acids
Give the IUPAC name for each carboxylic acid.
11
IUPAC Names for Carboxylic Acids
Step 1 Identify the longest carbon chain and add “anoic acid” to the end of the base name (for the straight chain acids). butanoic acid benzoic acid
12
IUPAC Names for Carboxylic Acids
Step 2 Give the location and name of each substituent by counting the carboxyl carbon as 1. a. 2-methylbutanoic acid b. 3-chlorobenzoic acid 2-methylbutyric acid meta-chlorobenzoic acid
13
Alpha Hydroxy Acids Alpha hydroxy acids (AHAs) occur naturally in fruit, milk, and sugar cane. are used in skin care products.
14
Learning Check Give the IUPAC or common names for each of the following…. A. B. C.
15
Solution A. ethanoic acid (acetic acid) B. C. 2-Methylpropanoic acid
2-Bromobenzoic acid (o-bromobenzoic acid)
16
Learning Check Give the IUPAC and common names for the following… A. B. C.
17
Solution A. B. C. propanoic acid (propionic acid)
3-Methylbutanoic acid (methylbutyric acid) 3-Bromobenzoic acid (m-bromobenzoic acid)
18
Preparation of Carboxylic Acids
Carboxylic acids are prepared … by oxidizing primary alcohols or aldehydes. The example below shows the oxidation of ethanol, which produces ethanoic acid (acetic acid). © 2013 Pearson Education, Inc.
19
Learning Check A. butanoic acid B. propanoic acid
Which alcohol would be used to prepare the following? A. butanoic acid B. propanoic acid
20
Solution (it is the alcohol with the same number of carbons!) A. B.
21
Esters Esters … differ from carboxylic acids by the replacement of H in the hydroxyl group with an alkyl group. are fragrant components of many fruits, such as bananas, oranges, and strawberries. Yummy!
22
Esterification Esterification is the reaction of a carboxylic acid and alcohol in the presence of an acid catalyst to produce an ester. Insert esterification reaction pg 580
23
Acetylsalicylic Acid Aspirin
is used to relieve pain and reduce inflammation. is an ester of salicylic acid and acetic acid. is derived from the bark of a willow tree.
24
Acetylsalicylic Acid In 1899, Bayer chemical company in Germany produced an ester of salicylic acid and acetic acid, called acetylsalicylic acid (aspirin) that was less irritating to the stomach than salicylic acid.
25
Methyl Salicylate Oil of wintergreen is used to soothe sore muscles.
has a pungent, minty odor. is an ester of salicylic acid and methanol.
26
Esters in Plants Esters give flowers
and fruits their pleasant fragrances and flavors.
28
Naming Esters The name of an ester contains the names of
the alkyl group from the alcohol, and the carbon chain from the acid with -ate ending.
29
Example.. Give the IUPAC and common name of the following ester, responsible for the flavor and odor of pears. A hint is on the next slide…
30
Example.. Name the group on the oxygen first.
31
Example.. Name the group on the oxygen first: it is propyl.
Now count the number of carbons including the carbonyl carbon that are in the other side of the ester:
32
Example.. there are two carbons in the “acid” side of the ester, so the base name uses 2… So this is propyl ethanoate.
33
Learning Check Name the following ester. Hints are on the next few slides…
34
Learning Check Remember, you want to count the number of carbons on the oxygen first. Since there is one, our “group” is __________
35
Learning Check Remember, you want to count the number of carbons on the oxygen first. Since there is one, our “group” is methyl…
36
Learning Check Now you want to focus on the base name which comes from the carbonyl side of the compound… How many carbons are on this side?
37
Learning Check How many carbons are on this side? 4
So our base name is:
38
Learning Check How many carbons are on this side? 4
So our base name is: butanoate (that’s but for the 4 carbons and anoate because it is an ester).
39
Learning Check So the name of the compound is: Methyl butanoate.
40
Learning Check Here is another ester to try to name...click through the next few slides to work through this stepwise.
41
Learning Check Remember, we name the group on the oxygen first so the first part of the name is…
42
Learning Check Remember, we name the group on the oxygen first so the first part of the name is… ethyl
43
Learning Check Now we look at the number of carbons in the “acid” side :
44
Learning Check Now we look at the number of carbons in the “acid” side : 3 Since there are three, our base name is… Propanoate. Try to put the whole name together, then check your answer on the next slide.
45
Learning Check This is ethyl propanoate.
46
Learning Check Draw the condensed structural formula of the following ester. Take it one step at a time… What is the group on the oxygen? A. Ethyl pentanoate
47
Learning Check What is the group on the oxygen? The ethyl group is on the oxygen. How many carbons are in the base structure? A. Ethyl pentanoate
48
Learning Check How many carbons are in the base structure?
5 there are 5 carbons since the base name is pent… Now draw in your ester. I usually start by drawing the carbonyl with an oxygen attached…then add carbons where needed… A. Ethyl pentanoate
49
Learning Check A. Ethyl pentanoate
50
Learning Check Propyl butyrate So what is the group on the oxygen?
51
Learning Check Propyl butyrate How many carbons are in the base chain?
So what is the group on the oxygen? Propyl (3 carbons) How many carbons are in the base chain?
52
Learning Check Propyl butyrate
So what is the group on the oxygen? Propyl (3 carbons) How many carbons are in the base chain? 4
53
Learning Check Propyl butyrate The structure is…
54
Thank you for trying this online!
I will see you on Wednesday, October 15th. Extra credit opportunities: October 2oth help with National Chemistry Week activities…N-quad 11:15-1:15 October 30th : help with Halloween activity…B/C-quad (I think)…11:30-12:30. Note: dates & times are approximate…
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.