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Chapter 14
Carboxylic Acids and Carboxylic
Acid De rivative s
Denniston
Topping
Caret
5
th
Edition
Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Functional Group Formulas
14.1 Carboxylic Acids
Structure
•
Carboxylic acid groups consist of two
very polar functional groups
–
Carbonyl group
–
Hydroxyl group
•
Carboxylic acid groups are very polar
Carboxylic acid–Ester–
propanoic acidmethyl ethanoate
Physical Properties
•
Low molecular weight carboxylic acids
–
Sharp, sour taste
–
Unpleasant aromas
•
High molecular weight carboxylic acids
–
Fatty acids important in biochemistry
•
Low molecular weight carboxylic acids are water
soluble due to hydrogen bonding with:
–
Water
–
Each other
14.1 Carboxylic Acids
Physical Properties
Due to carboxylic acids forming intermolecular
hydrogen bonds boiling points are at higher
temperatures than those of any other functional
group studied
14.1 Carboxylic Acids
Nomenclature
•
Determine the parent compound: 4C – butane
•
Number the chain so that the carboxyl carbon
is carbon 1: from right to left
•
Replace the –e ending with –oic acid
–
Butanoic acid
–
If two carboxyl groups are present use –dioic acid
•
Complete naming as usual – bromine on C-3
CH
3
CH CH
2
C
Br
OH
O
14.1 Carboxylic Acids
1234
Carboxylic Acid
Naming Examples
14.1 Carboxylic Acids
Common Names
•
Use Latin or Greek prefixes
•
Suffix is –ic acid
•
Greek letters indicate the position of the
substituents
14.1 Carboxylic Acids
Names and Structures of Some
Common Carboxylic Acids
14.1 Carboxylic Acids
Some Important Carboxylic Acids
CH
3
CH
2
C
O
OH
16
Stearic acid
found in beef fat
14.1 Carboxylic Acids
[...]... proply • Parent carboxylicacid = ethanoic acid • Change suffix to reflect ester = Propyl ethanoate Naming Esters 14.2 Esters Naming esters is much like naming the salts of carboxylic acids: • Alkyl portion = first name ethyl • Parent carboxylic acid = ethanoic acid • Change suffix to reflect ester = Ethyl ethanoate Reactions Involving Esters 14.2 Esters Preparation • • • • Carboxylic acids react with... Carboxylic Acids • Nomenclature – First add the cation’s name • Sodium – Then drop the –oic acid and add –ate • Sodium benzoate • Uses of carboxylic acids • • • • Soaps like sodium stearate Preservatives Anti-fungal medicines Used to control food pH 14.1 Carboxylic Acids Esterification • Carboxylic acids react with alcohols to form: – Esters – Water 14.2 Esters Structure and physical properties • Esters... first name (Alcohol part of the ester) 2 Base the name for the acid part of the structure from the longest chain ending in the C=O (Carboxylic acid part of the ester) 3 Change the –oic acid of the acid name to –oate Naming Esters 14.2 Esters Name the following esters: • Alkyl portion = first name ethyl • Parent carboxylic acid = butanoic acid • Change suffix to reflect ester = Ethyl butanoate • Alkyl... Carboxylic Acids Acid- Base Reactions • Carboxylic acids DO react with strong bases to form carboxylate salts – A process of neutralization –Acid protons are removed by the –OH- to form H2O and carboxylate ion – Equilibrium shifts to the right with removal of H+ 14.1 Carboxylic Acids Using Acid- Base Reactions • What is the product of each of the following reactions? 14.1 Carboxylic Acids Salts of Carboxylic. .. 14.3 Acid Chlorides and AcidAcid Anhydride Reactions With Alcohols • Acid anhydride reacts with alcohol to produce: –Ester– Carboxylic acid – An acyl group transfer reaction O O CH3C O C CH3 + CH3 HO CH CH3 CH3 O CH3C O CH + CH3 O HO C CH3 14.4 Nature’s High Energy Compounds: Phosphoesters and Thioesters • Phosphoric acid reacts with alcohols to produce a phosphate ester or phosphoester • The ester. .. and requires heat • Mineral acid is used as a catalyst 14.2 Esters Acid hydrolysis of Esters Acid hydrolysis products are: • Acid • Alcohol 14.2 Esters Base hydrolysis of Esters The base catalyzed hydrolysis of an ester: • Saponification or soap-making • Products are: –Acid salt – Alcohol • Acid can’t exist in basic conditions, so the product is the salt of the carboxylic acid using the cation of the...14.1 Carboxylic Acids Reactions Involving Carboxylic Acids • Carboxylic acids are prepared by oxidation of primary alcohols and aldehydes CH3CH2CH2OH O H2CrO4 O CH3CH2C OH Warm CH3CH2CH 14.1 Carboxylic Acids Acid- Base Reactions • Carboxylic acids behave as acids because when they are dissolved in water they will deprotonate to form a carboxylate ion and the hydronium ion • Carboxylic acids are weak acids... Symmetrical anhydrides are named by replacing the -acid ending of the acid with – anhydride O O CH3C O C CH3 ethanoic anhydride acetic anhydride Anhydrides 14.3 Acid Chlorides and Acid Formation of Acid Anhydrides • Acid anhydrides are not typically formed in a reaction between the parent carboxylic acids • One pathway is the reaction between: –Acid chloride – Carboxylate anion O O O O warm + HO C CH CH3C... O Acid Anhydrides 14.3 Acid Chlorides and Hydrolysis of Acid Chlorides Acid chlorides react violently with water in a hydrolysis reaction • Reforming the acid and HCl • Substitution of the –OH for the –Cl occurs at the acyl carbon O CH3CH2C Cl + H2O Substitution O here CH3CH2C OH +HCl Acid Anhydrides 14.3 Acid Chlorides and Acid Chloride Substitution • Acid chlorides react with alcohols to form esters... CH2CH2OH 14.2 Esters HOOC Terphthalic acid HOOC * O C H+ 1,2-ethanediol O C O CH2CH2OH + H2O Continued condensation at each end O C O CH2CH2O n* PETE is used in: Repeating unit of the polymer •Mylar •Plastic bottles •Polyester fabric 14.3 Acid Chlorides and Acid Anhydrides • Acid chlorides are derivatives of carboxylic acids having the general formula: • Are named: – by replacing the –oic acid ending . polar
Carboxylic acid – Ester –
propanoic acid methyl ethanoate
Physical Properties
•
Low molecular weight carboxylic acids
–
Sharp, sour taste
–
Unpleasant. food pH
14.1 Carboxylic Acids
Esterification
•
Carboxylic acids react with alcohols to form:
–
Esters
–
Water
14.1 Carboxylic Acids
14.2 Esters
Structure