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Carboxylic acid – ester – propanoic acid methyl ethanoate

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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 acid methyl 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 carboxylic acid = 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 Acid Acid 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

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