Carboxylic Acids Nitriles Natural Products Nomenclature Acidity Preparation Reactions Analgesics CO 2H O OCCH3 (S)(+)ibuprofin acetyl salicylic acid HO 2C Fats and Fatty Acids CO 2H palmitic acid (a fatty acid) O CH2 OCR O CH OCR O CH2 OCR a triglyceride R =
Download ReportTranscript Carboxylic Acids Nitriles Natural Products Nomenclature Acidity Preparation Reactions Analgesics CO 2H O OCCH3 (S)(+)ibuprofin acetyl salicylic acid HO 2C Fats and Fatty Acids CO 2H palmitic acid (a fatty acid) O CH2 OCR O CH OCR O CH2 OCR a triglyceride R =
Carboxylic Acids Nitriles Natural Products Nomenclature Acidity Preparation Reactions Analgesics CO 2H O OCCH3 (S)(+)ibuprofin acetyl salicylic acid HO 2C Fats and Fatty Acids CO 2H palmitic acid (a fatty acid) O CH2 OCR O CH OCR O CH2 OCR a triglyceride R = n-C15H31 Prostaglandins cycloCO2H oxygenase O CO2H HO arachadonic acid a prostaglandin OH natural mediators of inflammation Penicillins from mold Penicillium chrysogenum O PhCHCNH R S N O CO2H R = H penicillin G R= NH2 ampicillin From Ergot Fungus HO2C CH3 N H (+) lysergic acid NH Common Nomenclature Prefix form HCO 2H acet CH3CO2H propion butyr valer CO2H CO2H CO2H prefix + ic + _acid Cl CO2H -chlorovaleric acid capro enant h capryl pelargon capr CO2H CO2H CO2H CO2H CO2H CO2H Cl Cl dich l oro-ph e n yl capryli c acid I.U.P.A.C. Nomenclature drop e from alkane and add "oic acid" O OH heptanoic acid CO2H (Z) 2-methyl-2-pentenoic a CH2CO2H CO2H cyclopentanecarboxylic acid Br p-bromophenylet hanoic acid p-bromophenylacetic acid Dicarboxylic Acids oxalic acid HO2CCO2H or et hanedioic acid malonic acid HO2CCH2CO2H succinic acid HO2CCH2CH2CO2H glut aric acid ' HO2CCH2CH2CH2CO2H adipic acid HO2CCH2CH2CH2CH2CO2H pimelic acid HO2CCH2CH2CH2CH2CH2CO2H A Diacid O OH HO Br Cl O -bromo-'-chloroadipic acid 2-bromo-4-chlorohexanedioic acid Unusually High Melting and Boiling Points Boiling Points o b.p. C O CH3COH CH3CH2CH2OH 118 97 O CH3CH2CH 49 CH3CH2OCH3 8 Acidity is due to Delocalization of the Charge in the Conjugate Base Alcohol vs. Acid e Withdrawing Groups Enhance Acidity Benzoic acids CO 2H CO 2H CO 2H CO 2H CO 2H NO 2 CHO Cl H OCH3 3.75 4.0 4.19 4.46 pKa: 3.41 most deactivated most activat Deprotonation O O COH CO Na + NaHCO3 pKa 4.2 + H2CO3 pKa 6.5 Ester Formation O O COH 1) NaOH COCH2CH2CH2CH3 2) CH3CH2CH2CH2Br p.t.c. Carboxylic Acid Preparations • Oxidation of 1o alcohols and aldehydes with Na2Cr2O7/H2SO4 • KMnO4 oxidation of alkylbenzenes • Grignard reaction with CO2 (Carboxylation) • Hydrolysis of a carboxylic derivative: e.g. acid chloride, acid anhydride, ester, amide, nitrile Grignard Reaction with CO2 Br 1) Mg, ether 2) CO2, -78oC + 3) H3O CO2H Mechanism Br CO2H 1) Mg, ether 2) CO2, -78oC + 3) H3O Mg MgBr H + O O C C O O MgBr Hydrolysis of a Nitrile Br KCN SN2 + H3O CN or 1) NaOH + 2) H3O CO2H Reduction of Carboxylic Acids Naming Nitriles CH3 CH3CHCH2CH2CN CN 4-m e th yl pe n tan e n itri le cycloh e xan e carbon i tril e CN CN 5-h e xyn e n itri le Cl p-ch lorobe n z on itri le Dehydration of an Amide use strong dehydrating agent or SO Cl2 + H2O Reduction of Nitriles 1) LiAlH 4 CN 2) H 2O CH2NH2 Grignard Addition to a Nitrile CN O 1) CH3MgBr + CH3 2) H3O , heat heptanenitrile 2-octanone + NH3 Partial Mechanism C N 1) CH3MgBr O + 2) H3O , heat pH = 4-5 CH3 + NH3 CH3 C H N + H3O + H3O CH3 C an imine imine hydrolysis N H The Rest of the Mechanism CH3 H3O CH3 + N H H O + CH3 CH3 N H H H 2O CH3 H O H2O int ermolec. + H t ransfer CH3 NH2 O H NH3 O H H