Oxidation and Antioxidants in Organic Chemistry and Biology © 2005 by Taylor & Francis Group. Oxidation and Antioxidants in Organic Chemistry and Biology Evgeny T. Denisov Igor B. Afanas’ev Boca Raton London New York Singapore A CRC title, part of the Taylor & Francis imprint, a member of the Taylor & Francis Group, the academic division of T&F Informa plc. © 2005 by Taylor & Francis Group. Denisov/OxidationandAntioxidantsinOrganicChemistryandBiology DK1162_prelims FinalProof page iv 25.2.2005 11:11am Publishedin2005by CRCPress Taylor&FrancisGroup 6000BrokenSoundParkwayNW BocaRaton,FL33487-2742 (cid:1)2005byTaylor&FrancisGroup CRCPressisanimprintofTaylor&FrancisGroup NoclaimtooriginalU.S.Governmentworks PrintedintheUnitedStatesofAmericaonacid-freepaper 10987654321 InternationalStandardBookNumber-10:0-8247-5356-9(Hardcover) InternationalStandardBookNumber-13:978-0-8247-5356-6(Hardcover) LibraryofCongressCardNumber2004059305 Thisbookcontainsinformationobtainedfromauthenticandhighlyregardedsources.Reprintedmaterialisquoted withpermission,andsourcesareindicated.Awidevarietyofreferencesarelisted.Reasonableeffortshavebeenmade to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validityofallmaterialsorfortheconsequencesoftheiruse. Nopartofthisbookmaybereprinted,reproduced,transmitted,orutilizedinanyformbyanyelectronic,mechanical, orothermeans,nowknownorhereafterinvented,includingphotocopying,microfilming,andrecording,orinany informationstorageorretrievalsystem,withoutwrittenpermissionfromthepublishers. Forpermissiontophotocopyorusematerialelectronicallyfromthiswork,pleaseaccesswww.copyright.com(http:// www.copyright.com/)orcontacttheCopyrightClearanceCenter,Inc.(CCC)222RosewoodDrive,Danvers,MA 01923,978-750-8400.CCCisanot-for-profitorganizationthatprovideslicensesandregistrationforavarietyofusers. FororganizationsthathavebeengrantedaphotocopylicensebytheCCC,aseparatesystemofpaymenthasbeen arranged. TrademarkNotice:Productorcorporatenamesmaybetrademarksorregisteredtrademarks,andareusedonlyfor identificationandexplanationwithoutintenttoinfringe. LibraryofCongressCataloging-in-PublicationData Denisov,E.T.(EvgenyTimofeevich) Oxidationandantioxidantsinorganicchemistryandbiology/EvgenyT.Denisov,IgorB. Afanas’ev. p.cm. Includesbibliographicalreferencesandindex. ISBN0-8247-5356-9(alk.paper) 1. Hydrocarbons–Oxidation. 2. Antioxidants. 3. Chemistry, Organic. 4. Biology I.Afanas’ev,IgorB.,1935-II.Title. QD305.H5D342004 547’.0104593–dc22 2004059305 VisittheTaylor&FrancisWebsiteat http://www.taylorandfrancis.com andtheCRCPressWebsiteat Taylor & Francis Group is the Academic Division of T&F Informa plc. http://www.crcpress.com © 2005 by Taylor & Francis Group. Denisov/OxidationandAntioxidantsinOrganicChemistryandBiology DK1162_prelims FinalProof page v 25.2.2005 11:11am Dedication We dedicate this book to the memory of pioneers of Oxidation Chemistry, Aleksey Nikolaevich Bach and Nikolay Aleksandrovich Shilov © 2005 by Taylor & Francis Group. Denisov/OxidationandAntioxidantsinOrganicChemistryandBiology DK1162_prelims FinalProof page vii 25.2.2005 11:11am Table of Contents Preface Authors List of ChemicalSymbols andAbbreviations List of Physicochemical Symbols List of Biochemical Abbreviations Part I Chemistryand Kinetics of OrganicCompounds Oxidation by Dioxygen Chapter 1 Molecular Productsand Thermochemistry ofHydrocarbon Oxidation 1.1 Earlier Concepts ofOxidation 1.2 Development of the Chain Theoryof Oxidation of OrganicCompounds 1.3 Hydroperoxides asPrimary Molecular Products ofHydrocarbon Oxidation 1.3.1 Hydroperoxides 1.3.2 Dihydroperoxides 1.3.3 Cyclicand Polymeric Peroxides 1.3.4 Epoxides 1.4 Products of Hydroperoxide Decomposition 1.4.1 Hydroperoxidesas the Intermediates of Hydrocarbon Oxidation 1.4.2 Alcohols 1.4.3 Ketones 1.4.4 Acids References Chapter 2 Chain Mechanismof Liquid-Phase Oxidation of Hydrocarbons. 2.1 The Peculiarities ofChain Reactions 2.1.1 Free-Valence Persistence in Reactions ofFreeRadicals withMolecules 2.1.2 Condition ofCyclicityof RadicalConversions 2.1.3 Priority of Chain Propagation Reaction 2.1.4 Generation ofFreeRadicals. 2.1.5 Competition of Chain and Molecular Reactions 2.1.5.1 High Chemical Reactivityof Free Radicals and Atoms 2.1.5.2 Conservation of Orbital Symmetry inChemical Reaction 2.1.5.3 Configuration ofTransition State. 2.2 Chain Mechanism of Hydrocarbon Oxidation 2.3 Reaction of Alkyl Radicals with Dioxygen 2.4 Reactions of Peroxyl Radicals 2.4.1 Structure and Thermochemistry of PeroxylRadicals 2.4.2 Reaction RO .þRH ! ROOHþR. 2 2.4.3 Intramolecular HydrogenAtom Transferin Peroxyl Radical 2.4.4 Addition ofPeroxylRadicalto theDoubleBond © 2005 by Taylor & Francis Group. Denisov/OxidationandAntioxidantsinOrganicChemistryandBiology DK1162_prelims FinalProof page viii 25.2.2005 11:11am 2.5 Chain Termination in Oxidized Hydrocarbons 2.5.1 Tetroxide 2.5.2 Disproportionation ofTertiary Peroxyl Radicals 2.5.3 Disproportionation ofPrimary and Secondary Peroxyl Radicals 2.5.4 Chemiluminescence 2.5.5 Chain Termination viaAlkylRadicals 2.6 Reactionsof AlkoxylRadicals 2.7 DifferentMechanismsof theAliphatic Hydrocarbon Oxidation inGas and LiquidPhases References Chapter 3 Initiation ofLiquid-Phase Oxidation. 3.1 Initiators 3.1.1 Mechanismsof Decomposition of Initiators 3.1.1.1 UnimolecularDecompositionofInitiatorwithOneBondSplitting 3.1.1.2 Concerted Fragmentation of Initiators 3.1.1.3 AnchimericallyAssisted Decomposition ofPeroxides 3.1.2 Decay of Initiatorsto Molecular Produ 3.1.3 Chain Decomposition of Initiators 3.1.4 Peroxides 3.1.5 Azo-Compounds 3.2 Cage Effect 3.2.1 Experimental Evidencesfor Cage Effect 3.2.1.1 Quantum Yield 3.2.1.2 Products of Radical Pair Combination 3.2.1.3 Oxygen-18 Scrambling and Racemization 3.2.1.4 CrossoverExperiments 3.2.1.5 Racemization 3.2.1.6 Influence ofViscosity 3.2.1.7 Influence ofPressure. 3.2.1.8 Spin Multiplicity Effects 3.2.2 Mechanistic Schemes ofthe Cage Effect 3.3 Initiation ofOxidation by Chemically Active Gases 3.3.1 Ozone 3.3.2 Nitrogen Dioxide 3.3.3 Halogens 3.4 Photoinitiation 3.4.1 Intramolecularand Intermolecular Photophysical Processes 3.4.2 Photosensitizers 3.4.3 Photoinitiators 3.4.3.1 Azo-compounds 3.4.3.2 Peroxides 3.4.3.3 CarbonylCompounds 3.4.4 Nonchain Photooxidation 3.5 Generation ofRadicals by Ionizing Radiation 3.5.1 Primary Radiation–Chemical Processes 3.5.2 Radiolytic Initiation ofHydrocarbon Oxidation References © 2005 by Taylor & Francis Group. Denisov/OxidationandAntioxidantsinOrganicChemistryandBiology DK1162_prelims FinalProof page ix 25.2.2005 11:11am Chapter 4 Oxidation as an Autoinitiated Chain Reaction 4.1 Chain Generation by Reaction of Hydrocarbon with Dioxygen 4.1.1 Bimolecular Reaction of Dioxygenwiththe C HBond of the Hydrocarbon 4.1.2 Trimolecular Reaction ofHydrocarbon with Dioxygen 4.1.3 Bimolecular and Trimolecular Reactionsof Dioxygen with theDouble Bond of Olefin 4.2 Hydroperoxides 4.2.1 Analysis 4.2.2 Structure ofHydroperoxides 4.2.3 Thermochemistry ofHydroperoxides 4.2.4 HydrogenBonding between Hydroperoxides 4.3 Reactions of Free Radical Generation by Hydroperoxides 4.3.1 UnimolecularDecomposition of Hydroperoxides 4.3.2 Bimolecular Decomposition of Hydroperoxides 4.3.3 Bimolecular Reactions ofHydroperoxideswithp-Bonds of Olefins 4.3.4 Bimolecular Reactions ofHydroperoxideswithC H, N H, and O(cid:1)(cid:1)H Bonds ofOrganicCompounds 4.4 Parabolic Model ofBimolecular Homolytic Reaction 4.4.1 MainEquationsof IPM 4.4.2 Calculation of E and kof aBimolecular Reaction 4.4.3 Bimolecular Reactions ofRadical Generation 4.4.3.1 Bimolecular Splitting of Hydroperoxides. 4.4.3.2 Reaction of Hydroperoxides with Olefins 4.4.3.3 Reaction of Hydroperoxides with Hydrocarbons 4.4.3.4 Reaction of Hydroperoxides with Alcoholsand Acids 4.5 Initiationby Reaction ofHydroperoxides withKetones 4.6 Chain Decomposition ofHydroperoxides 4.7 Kinetics ofAutoinitiated Hydrocarbon Oxidation 4.7.1 Initial Stage ofAutoxidation 4.7.2 Autoxidation withBimolecular Hydroperoxide Decay 4.7.3 Initiation by Reactions of Hydroperoxide with Products ofOxidation 4.7.4 Hydroperoxide as the Intermediate Product of Autoxidation 4.7.5 Self-Inhibition of Hydrocarbon Oxidation References Chapter 5 Co-Oxidation ofHydrocarbons 5.1 Theory of Hydrocarbon Co-oxidation 5.2 Hydrocarbon Oxidation withHydroperoxide 5.3 Co-oxidation ofHydrocarbons and AlcoholswithSelectiveInhibitor 5.4 Cross-disproportionation of PeroxylRadicals 5.5 Cross-propagation Reactions of Peroxyl Radicals 5.6 High Reactivity ofHaloidalkylperoxyl Radicals 5.7 Co-oxidation ofHydrocarbon and its Oxidation Intermediates 5.8 Catalysisby Nitroxyl Radicals inHydrocarbon Oxidation References © 2005 by Taylor & Francis Group. Denisov/OxidationandAntioxidantsinOrganicChemistryandBiology DK1162_prelims FinalProof page x 25.2.2005 11:11am Chapter 6 Reactivity ofthe Hydrocarbons in Reactions with Peroxyl, Alkoxyl, and AlkylRadicals 6.1 Semiempirical Model ofRadicalReaction asan Intersection of Two Parabolic PotentialCurves 6.1.1 Introduction 6.1.2 IntersectingParabolas Model(IPM) 6.1.3 Calculation of theActivation Energy 6.2 Factors Influencingthe Activation Energ 6.2.1 Reaction Enthalpy 6.2.2 Force Constants ofthe Reacting Bonds 6.2.3 Triplet Repulsionin theTransition State 6.2.4 Electron Affinityof Atomsof Reaction Center 6.2.5 Radii ofAtomsof Reaction Center 6.2.6 Influence of Adjacentp-Bonds 6.2.7 PolarEffec 6.2.8 Influence of Solvation 6.3 Geometryof the Transition State of RadicalAbstraction Reaction 6.4 Intramolecular Hydrogen Transfer Reactions in Peroxyl, Alkoxyl, and AlkylRadicals. 6.4.1 PeroxylRadicals 6.4.2 Alkoxyl Radicals 6.4.3 Alkyl Radicals 6.5 Free RadicalAdditionReactions 6.5.1 Enthalpy ofFreeRadicalAddition. 6.5.2 Parabolic Modelof RadicalAdditionReaction 6.5.3 Triplet Repulsionin RadicalAddition Reactions 6.5.4 Influence of theNeighboringp-Bonds on the Activation Energy of RadicalAddition 6.5.5 Role ofthe Radius ofthe Atom Bearing a Free Valence 6.5.6 Interaction ofPolarGroups 6.5.7 Steric Hindrance 6.6 Free RadicalSubstitution and Hydrogen Atom Transfer Reactions 6.6.1 Free Radical Substitution Reactions 6.6.2 Reaction ofPeroxides withKetylRadicals References Chapter 7 Oxidation of Alcoholsand Ethers 7.1 Oxidation of Alcohols 7.1.1 Introduction 7.1.2 Chain Mechanism ofAlcohol Oxidation 7.1.2.1 Kinetics ofOxidation 7.1.2.2 Reactionsof Ketyl Radicals with Dioxygen 7.1.2.3 Reactionsof Alkylhydroxyperoxyland Hydroperoxyl Radicals 7.1.2.4 Chain Termination in Oxidized Alcohols 7.1.3 Co-Oxidation of Alcoholsand Hydrocarbons 7.1.4 Reactivity ofAlcohols inReaction with Peroxyl Radicals © 2005 by Taylor & Francis Group. Denisov/OxidationandAntioxidantsinOrganicChemistryandBiology DK1162_prelims FinalProof page xi 25.2.2005 11:11am 7.1.5 Chain Generation in Autoxidation of Alcohols 7.1.5.1 Chain Generation by Reaction with Dioxygen 7.1.5.2 Decomposition of Hydrogen Peroxideinto Free Radicals 7.1.5.3 Chain Generation by Reaction of Hydrogen Peroxide with CarbonylCompound 7.2 Oxidation of Ethers 7.2.1 Introduction 7.2.2 Chain Oxidation ofEthers 7.2.3 Co-Oxidation of Ethers and Hydrocarbons 7.2.4 Reactivity ofEthersin Reactions with Peroxyl Radicals References Chapter 8 Oxidation of CarbonylCompounds and Decarboxylation of Acids 8.1 Oxidation of Aldehydes 8.1.1 Introduction 8.1.2 Chain Mechanism ofAldehyde Oxidation 8.1.3 Co-Oxidation of Aldehydeswith Hydrocarbons,Alcohols, andAldehydes 8.1.4 Reactivity ofAldehydes in Reactions with Peroxyl Radicals 8.2 Chemistryof Peracids 8.3 Oxidation of Ketones. 8.3.1 Chain Mechanism ofKetone Oxidation 8.3.2 Reactivity ofKetones inReactions withPeroxylRadicals 8.3.3 Interactionof Ketones with Hydroperoxides 8.3.4 Chemistry ofKetone Oxidation 8.4 Oxidative Decarboxylation of Carboxylic Acids 8.4.1 Attack of PeroxylRadicals on C(cid:1)(cid:1)H Bond 8.4.2 Oxidative Decarboxylation ofAcids References Chapter 9 Oxidation of Amines, Amides, andEsters 9.1 Oxidation of Aliphatic Amines 9.1.1 Introduction 9.1.2 Chain Mechanism ofAlkylamine Oxidation 9.1.3 Reactivity ofAminesin Reaction with PeroxylRadicals 9.2 Oxidation of Amides 9.2.1 Introduction 9.2.2 Chain Mechanism ofAmideOxidatio 9.2.3 Decomposition ofHydroperoxides 9.3 Oxidation of Esters 9.3.1 Introduction 9.3.2 Chain Mechanism ofEster Oxidation 9.3.3 Reactivity ofEsters inReactionswithPeroxylRadicals 9.3.4 Effect of Multidipole Interaction inReactionsof PolyfunctionalEsters References © 2005 by Taylor & Francis Group.