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Introduction to Organic Chemistry and BiochemistryIntroduction to Organic Chemistry and Biochemistry Instructor Dr. Upali Siriwardane (Ph.D. Ohio State) E-mail: upali@chem.latech.edu Office: 311 Carson Taylor Hall ; Phone: 318-257-4941;Office Hours: MTW 9:00 am - 11:00 am; TR 9::00 - !0:00 am & 1:00-2:00 pm.December 19, Test 1 (Chapters 12-14)January 2 Test 1 (Chapters 15-16)February 6 (Chapters 17-19)February 27, (Chapters 20-22)March 2, 2009, Make Up Exam:Bring Scantron Sheet 882-E

Chemistry 121(01) Winter 2009

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Chapter 16: Carboxylic Acids, Esters, and Chapter 16: Carboxylic Acids, Esters, and Other Acid DerivativesOther Acid Derivatives

SectionsSections

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Chapter 16:Carboxylic Acids, Esters, and Other Chapter 16:Carboxylic Acids, Esters, and Other Acid DerivativesAcid Derivatives16.1 Structure of Carboxylic Acids and Their Derivatives16.1 Structure of Carboxylic Acids and Their Derivatives

16.2 IUPAC Nomenclature for Carboxylic Acids16.2 IUPAC Nomenclature for Carboxylic Acids

16.3 Common Names for Carboxylic Acids16.3 Common Names for Carboxylic Acids

16.4 Polyfunctional Carboxylic Acids16.4 Polyfunctional Carboxylic Acids

16.5 "Metabolic" Acids16.5 "Metabolic" Acids

16.6 Physical Properties of Carboxylic Acids16.6 Physical Properties of Carboxylic Acids

16.7 Preparation of Carboxylic Acids16.7 Preparation of Carboxylic Acids

16.8 Acidity of Carboxylic Acids16.8 Acidity of Carboxylic Acids

16.9 Carboxylic Acid Salts16.9 Carboxylic Acid Salts

16.11 Preparation of Esters16.11 Preparation of Esters

16.14 Isomerism for Carboxylic Acids and Esters16.14 Isomerism for Carboxylic Acids and Esters

16.16 Chemical Reactions of Esters16.16 Chemical Reactions of Esters

16.18 Polyesters16.18 Polyesters

16.19 Acid Chlorides and Acid Anhydrides16.19 Acid Chlorides and Acid Anhydrides

16.20 Esters and Anhydrides of Inorganic Acids16.20 Esters and Anhydrides of Inorganic Acids

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Carboxylic Acids and Acid Derivatives

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Nomenclature of Carboxylic Acids

The IUPAC system deals with carboxylic acids similar to aldehydes.

Carboxyl group takes priority and it’s carbon assigned the number one.

Suffix: for -ane ending, drop -e and add -oic acid.

There are two ways to identify substituent carbons in carboxylic acid: numbers or Greek letters.

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Carboxylic acid examples

• 2-bromopropanoic acid (or -bromopropanoic acid) • 2-methyl butenoic acid • 2,2-dibromopropanoic acid • or , -dibromopropanoic acid or 3-oxopentanoic

acid or 3-ketopentanoic acid - ketopentanoic acid • methanoic acid H-COOH (formic acid)• ethanoic acid CH3COOH (acetic acid)• benzoic acid Ar-COOH

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Nomenclature of Esters

Alkyl(R') alkan(R)oate (a two-part name)

R’= Alkyl (R') group is attached to the O

methylethanolate

isopropylbenzoate

ethylbutanolate

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Nomenclature of acid halides

Alkanoyl halide (-oyl halide suffix)

or use common acyl name from acid

E.g. chloride of proponoic acid is named as proponoyl chloride

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Alkanoic anhydride (-oic anhydride suffix)

E.g. anhydride of proponoic acid is named as proponoic anhydride

Nomenclature of Acid Anhydrides

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Metal alkanoate (-oate suffix for anion)

E.g. sodium salt of proponoic acid is

named as sodium proponate

Nomenclature of Carboxylate salts

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Physical properties of carboxylic acidsCarboxyl groups exhibit very strong hydrogen bonding.

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Acidity

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Preparation of carboxylic acids Oxidation of primary alcohol to carboxylic acid.

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Tollen’s and Benedict’s

Oxidation of alkyl side chain substituted on a benzene ring

Oxidation of Aldehydes

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•Hydrolysis of acid chlorides

•Hydrolysis of acid anhydrides

Hydrolysis of esters.

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Carboxylic Acids

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Preparation of esters. Esterification

acid + alcohol ----> ester + H2O

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Esters as Flavors

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Fatty acids and GlyceridesFatty Acids

Glycerides

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Hydrolysis of Glycerides: Saponification

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Reactions of -keto acids.

-keto acids are readily decarboxylated.

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Oxidation of primary alcohols

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Oxidation of secondary and tertiary alcohols