Review of Organic Functional Groups Functional Group Analysis

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Review of Organic Functional Groups (Functional Group Analysis) Chapter 11 Carboxylic Acids Copyright ©

Review of Organic Functional Groups (Functional Group Analysis) Chapter 11 Carboxylic Acids Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Functional Group Analysis Carboxylic Acids Nomenclature Common name IUPAC name Formic acid Methanoic acid

Functional Group Analysis Carboxylic Acids Nomenclature Common name IUPAC name Formic acid Methanoic acid Acetic acid (vinegar) Ethanoic acid Propionic acid cis or Z stereochemistry Lauric acid w-3 3 1 NOTE: Z stereochemistry of natural products 2 Stearic acid Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Functional Group Analysis Carboxylic Acids Physical-Chemical Properties 1. Bonding: Dipole-dipole van der Waal Dipole-dipole

Functional Group Analysis Carboxylic Acids Physical-Chemical Properties 1. Bonding: Dipole-dipole van der Waal Dipole-dipole Intermolecular bonding - self Intermolecular H 2 O bonding High boiling points/melting points Carboxyl solubilizing potential ~3 carbons(polyfunctional molecule) Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Functional Group Analysis Carboxylic Acids Physical-Chemical Properties 1. Bonding: Ethanol as a pharmaceutical solvent

Functional Group Analysis Carboxylic Acids Physical-Chemical Properties 1. Bonding: Ethanol as a pharmaceutical solvent Improved solubility Dipole-dipole van der Waal 2. Acidity: The ability of a substance to donate a proton. R - electron withdrawing R - electron donating Stability of anion acidity Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins acidity

Functional Group Analysis Carboxylic Acids Role of Electron Withdrawing/Releasing Groups on Acidity Substituted Carboxylic

Functional Group Analysis Carboxylic Acids Role of Electron Withdrawing/Releasing Groups on Acidity Substituted Carboxylic acids Alkylcarboxylic acids Substituent Affects Electron donors/release R= Actual p. Ka H- p. Ka = 3. 75 CH 3 - p. Ka = 4. 76 p. Ka = 4. 87 C 2 H 5 Electron-withdrawing alkyl Arylcarboxylic acids p. Ka = 0. 64 CCl 3 - Electron withdrawing aryl p. Ka = 4. 21 p. Ka = 3. 44 p. Ka = 4. 38 Electron donors/release Inorganic acids (H 2 SO 4, HCl, HNO 3) >> Aryl acids >Alkyl acids > Phenol > Aryl amines > Alkyl amines Nearly total dissociation in water Weak dissociation in water Dissociation of conjugate acid in water Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Functional Group Analysis ACIDS p. H Consideration of Organic Functional Groups H 2 SO

Functional Group Analysis ACIDS p. H Consideration of Organic Functional Groups H 2 SO 4 HCl HNO 3 I n c r e a s i n g B a s i c i t y H 3 O RCO 2 H Ar. OH RSO 2 NH 2 OH O C N C H 2 O N Ar. NH 2 NH R C NH 2 I n c r e a s i n g A c i d i t y Alkyl NH 2 NH RHN C NH 2 Na. OH, KOH BASES Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Functional Group Analysis Carboxylic Acids Physical-Chemical Properties 3. Chemical reactivity: Salt formation Soluble salts

Functional Group Analysis Carboxylic Acids Physical-Chemical Properties 3. Chemical reactivity: Salt formation Soluble salts include: Insoluble salts include: p. H 7 Soluble salt’s affect on p. H of aqueous media Salt of a weak acid (organic acids are weak) p. H 7 Na. OH Salt of a strong base p. H 7 Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins p. H of aqueous media predicted to be alkaline

Functional Group Analysis Carboxylic Acids Metabolism -Phase 1: -oxidation b a Unbranched fatty acids

Functional Group Analysis Carboxylic Acids Metabolism -Phase 1: -oxidation b a Unbranched fatty acids -Phase 2: Glucuronidation UDPGA + Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Functional Group Analysis Carboxylic Acids Metabolism -Phase 2 Amino acid conjugation R-COOH + ATP

Functional Group Analysis Carboxylic Acids Metabolism -Phase 2 Amino acid conjugation R-COOH + ATP + Co. A Activated carboxylic acid R-CO-S-Co. A + AMP + Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins