Liquid-PhaseReaction Rate ConstantsE.T. DenisovInstituteof Chemical PhysicsMoscow,UssRTranslated fromRussianbyR.K.JohnstonIFI/PLENUMNEWYORK-WASHINGTON-LONDON
Liquid-Phase Reaction Rate Constants E. T. Deni soy Institute of Chemical Physics Moscow, USSR Translated from Russian by R. K. Johnston IFljPLENUM NEW YORK-WASHINGTON -LONDON
PREFACEThe past 25 years in chemical kinetics have seen majoradvancesin studying the mechanismsof complex chemical re-actions, in particular free radicalreactions.Many differ-ent methods have been developed for quantitative studies ofelementary chemical reactions.Thousands of rate constantshave been measured, for hundreds of diverse chemical reac.tions. It is becoming more and more difficult for the chemistto orient himself in the voluminous and rapidly growing liter-ature of chemical reaction kinetics.This leads to majorexpenditures of time in searchingout,collecting, and eval-uating quantitative kinetic data;to unnecessary repetition(duplication)of research; andsituation in which thetoarich material already accumulatedin the field of chemicalkinetics is very often not fully utilized in comparing,interpreting, and analyzingnewexperimental data. There isa pressing need for the creationof a series of handbooks onreaction rate constants.Suchworkwasbegunseveralyearsago at the initiative of V. N. Kondrat'ev, and is now goingforward under his direction atthe Institute of ChemicalPhysics of the USSR Academy of Sciences.This book is devoted to liquid-phase, homolytic reactions.Part One contains data on monomolecular reactions in whichmolecules decompose to formradicals, as wellas data on bi-molecular and trimolecular reactions that form free radicals.Also collected in PartOnedataareon theprobability ofradical escape into the bulkvolumefrom a"cage" of solventas wellwith various initiatorsasvaluesof the stoichio-metric inhibition coefficientsforvariousphenols and aromaticamines that are used asfreeradicalacceptors.In Part Two,rate constants are collectedforreactions of decomposition,substitution, and additionofradicalsto molecules,as wellas radical recombinationand disproportionation reactions.Part Three contains dataon ion--molecule reactions that areaccompanied by radical formation, as well as reactions of
PREFACE The past 25 years in chemical kinetics have seen major advances in studyiqg the mechanisms of complex chemical reactions, in particular free radical reactions. Many different methods have been developed for quantitative studies of elementary chemical reactions. Thousands of rate constants have been measured, for hundreds of diverse chemical reactions. It is becoming more and more difficult for the chemist to orient himself in the voluminous and rapidly growing literature of chemical reaction kinetics. This leads to major expenditures of time in searching out, collecting. and evaluating quantitative kinetic data; to unnecessary repetition (duplication) of research; and to a situation in which the rich material already accumulated in the field of chemical kinetics is very often not fully utilized in comparing, interpreting, and analyzing new experimental data. There is a pressing need for the creation of a series of handbooks on reaction rate constants. Such work was begun several years ago at the initiative of V. N. Kondrat'ev, and is now going forward under his direction at the Institute of Chemical Physics of the USSR Academy of Sciences. This book is devoted to liquid-phase, homolytic reactions. Part One contains data on monomolecular reactions in which molecules decompose to form radicals, as well as data on bimolecular and trimolecular reactions that form free radicals. Also collected in Part One are data on the probability of radical escape into the bulk volume from a "cage" of solvent with various initiators, as well as values of the stoichiometric inhibition coefficients for various phenols and aromatic amines that are used as free radical acceptors. In Part Two, rate constants are collected for reactions of decomposition, substitution, and addition of radicals to molecules, as well as radical recombination and disproportionation reactions. Part Three contains data on ion-molecule reactions that are accompanied by radical formation, as well as reactions of v
viPREFACEfree radicals with metal ions and acid anions, reactions ofion-radicals and solvated electrons, and ionic oxidation-reduction reactions with electron transfer.In this book,rate constant values are presented along with a statementof the conditions and a brief characterization of the methodof measurement.I wish to express deep gratitude to AcademicianV.N.Kondrat'ev for having inspired me to this not easy butuseful task, and for having aided me with counsel.The lastchapter of this book was written by V. N. Berdnikov.Forassistance in collecting the reaction rateconstants,Ithank A,L,Buchachenko, R.L.Vardanyan, S. S. Ivanchev,N.F.Kazanskaya, G.M.Nazin, A.A.Shteinman, and V.Ya.Shlyapintokh.I also wish to express gratitute to Z.A.Denisova for painstaking work in preparing the manuscriptforpublication.E.T. Denisov
vi PREFACE free radicals with metal ions and acid anions, reactions of ion-radicals and solvated electrons, and ionic oxidationreduction reactions with electron transfer. In this book, rate constant values are presented along with a statement of the conditions and a brief characterization of the method of measurement. I wish to express deep gratitude to Academician V. N. Kondrat'ev for having inspired me to this not easy but useful task, and for having aided me with counsel. The last chapter of this book was written by V. N. Berdnikov. For assistance in collecting the reaction rate constants, I thank A. L. Buchachenko, R. L. Vardanyan, S. S. Ivanchev, N. F. Kazanskaya, G. M. Nazin, A. A. Shteinman, and V. Ya. Shlyapintokh. I also wish to express gratitute to Z. A. Denisova for painstaking work in preparing the manuscript for publication. E. T. Denisov
CONTENTSPrefacevxiiiList of TablesxxiiiSymbols.AbbreviationsxxVPART ONE-REACTIONS OF MOLECULES1CHAPTER I.MONOMOLECULAR REACTIONS1.Methods for Measuring Rate Constants3of Monomolecular Reactions2.Rate Constants for Decomposition of8PeroxideCompounds103.Decomposition of Azo Compounds4.Decomposition atC-C,N-N,N-C,10N-O,and C-Metal Bonds11Decompositionof Iodobenzene Dichloride5.116.Correlation Equations7.Effect of Pressure and Solvent on13Monomolecular Reactions87CHAPTER II.BIMOLECULAR AND TRIMOLECULAR REACTIONSl.Methods forMeasuringRateConstants87of Bimolecular Reactionsvi
CONTENTS Preface List of Tables Symbols Abbreviations • PART ONE - REACTIONS OF MOLECULES CHAPTER I. MONOMOLECULAR REACTIONS 1. Methods for Measuring Rate Constants of Monomolecular Reactions • 2. Rate Constants for Decomposition of Peroxide Compounds • • • 3. Decomposition of Azo Compounds • 4. Decomposition at C - C, N - N, N - C, N - 0, and C-Metal Bonds ••• 5. Decomposition of Iodobenzene Dichloride 6. Correlation Equations 7. Effect of Pressure and Solvent on Monomolecular Reactions v xiii xxiii xxv 1 3 8 10 10 11 11 13 CHAPTER II. BIMOLECULAR AND TRIMOLECULAR REACTIONS 87 1. Methods for Measuring Rate Constants of Bimolecular Reactions • • vii 87
viliCONTENTS892.Diels-Alder Reaction3.Bimolecular Reactions with Peroxide89Participation4.Oxidation-Reduction Reactions withParticipation of c102,02,91and C125.Reactions with Rupture of Metal-Carbon92Bond926.Trimolecular Reactions109CHAPTER III.THE CAGE EFFECT109l.Questions of Theory2.Methods for Measuring Initiator111Efficiency1143.Initiator Efficiency135LITERATURE CITED(PartOne)PART TWO -REACTIONSOF FREE ATOMS AND RADICALSCHAPTER IV.METHODSFOR MEASURING RATE CONSTANTS157OF RADICAL REACTIONSl. Measurement of Relative Rate Constants157of Radical Reactions2. Measurement of Absolute Rate Constantsof Reactions of Atoms and164RadicalsISOMERIZATIONAND DECOMPOSITION OFCHAPTER V.173FREE RADICALS173l.Isomerization of Free Radicals1742. Decomposition of Free Radicals
viii 2. Diels-Alder Reaction ••• 3. Bimolecular Reactions with Peroxide Participation 4. Oxidation-Reduction Reactions with Participation of Cl02, 02, and C12 • • • • • • 5. Reactions with Rupture of Metal-Carbon Bond .•.••• 6. Trimolecular Reactions. CHAPTER 111. THE CAGE EFFECT 1. Questions of Theory 2. Methods for Measuring Initiator Efficiency • 3. Initiator Efficiency • LITERATURE CITED (Part One) CONTENTS 89 89 91 92 92 109 109 111 114 135 PART TWO - REACTIONS OF FREE ATOMS AND RADICALS CHAPTER IV. METHODS FOR MEASURING RATE CONSTANTS OF RADICAL REACTIONS 1. Measurement of Relative Rate Constants of Radical Reactions 2. Measurement of Absolute Rate Constants of Reactions of Atoms and Radica Is . . . . . . . · . . . CHAPTER V. ISOMERIZATION AND DECOMPOSITION OF FREE RADICALS . . . . · 1. Isomerization of Free Radicals 2. Decomposition of Free Radicals · 157 157 164 173 173 174
CONTENTSix179CHAPTERVI.RADICAL SUBSTITUTION REACTIONS1791.Reactions of Atoms2.Reactions of Radicals Having Free181Valence on Oxygen3.Reactions of Radicals Having Free183Valence on Carbon4.183Chain Transfer in Radical Polymerization5.Reactions of Radicals Having Free184Valence on Nitrogen6.Correlation Equations for Radical184Substitution ReactionsADDITION REACTIONS OFATOMS ANDCHAPTER VII.351RADICALS1.Addition of Atoms and Radicals to351Molecular Oxygen3512.Addition at C=C Bond3533. Addition to Aromatic Compounds4.Addition to Quinones,CarbonylCompounds, Nitriles, and354Nitro CompoundsCHAPTER VIII.RECOMBINATIONANDDISPROPORTION-399ATIONOF FREE ATOMS AND RADICALS399l.Recombination ofAtoms2.Disproportionation and Recombination399of Alkyl and Ro*Radicals4013.Reactions between Peroxy Radicals4.Reactions of Radicals Having Free402Valence on Nitrogen or Tin
CONTENTS CHAPTER VI. RADICAL SUBSTITUTION REACTIONS 1. Reactions of Atoms ••••• 2. Reactions of Radicals Having Free Valence on Oxygen • • • • 3. Reactions of Radicals Having Free Valence on Carbon •••• 4. Chain Transfer in Radical Polymerization 5. Reactions of Radicals Having Free Valence on Nitrogen 6. Correlation Equations for Radical Substitution Reactions • • CHAPTER VII. ADDITION REACTIONS OF ATOMS AND RADICALS • • • • 1. Addition of Atoms and Radicals to Molecular Oxygen 2. Addition at C = C Bond ••• 3. Addition to Aromatic Compounds • 4. Addition to Quinones, Carbonyl Compounds, Nitriles, and Nitro Compounds • • • • CHAPTER VIII. RECOMBINATION AND DISPROPORTIONix 179 179 181 183 183 184 184 351 351 351 353 354 ATION OF FREE ATOMS AND RADICALS • 399 1. Recombination of Atoms 2. Disproportionation and Recombination of Alkyl and RO· Radicals 3. Reactions between Peroxy Radicals 4. Reactions of Radicals Having Free Valence on Nitrogen or Tin 399 399 401 402
xCONTENTS5.Reactions between Free Radicals of402Different TypesCHAPTERIX.EFFECT OF SOLVENT ON FREERADICAL427REACTIONS1.427Solvent Viscosity2.427Internal Pressure of Liquid3.428Nonspecific Solvation4304.Hydrogen Bond between Molecules4315.Radical Hydrogen Bond4326.Formation of T-Complexes443(Part Two)LITERATURE CITEDPART THREE-IONIC HOMOLYTIC REACTIONSCHAPTER X.OXIDATION-REDUCTION REACTIONS OF479IONSWITHMOLECULES1.Oxidation of Organic Compounds by479Variable-Valence Metal Ions2.Reaction of Variable-Valence MetalIons with Oxygen, Peroxides,485and QuinonesCHAPTERXI.REACTIONSOFATOMSANDRADICALS531WITH IONS.5311.Reactions of Hydrogen Atom2.531Reactions of Free Radicals
x 5. Reactions between Free Radicals of Different Types CHAPTER IX. EFFECT OF SOLVENT ON FREE RADICAL REACTIONS 1. Solvent Viscosity 2. Internal Pressure of Liquid 3. Nonspecific Solvation 4. Hydrogen Bond between Molecules 5. Radical Hydrogen Bond 6. Formation of 7f-Complexes •• LITERATURE CITED (Part Two) ••• CHAPTER X. PART THREE - IONIC HOMOLYTIC REACTIONS OXIDATION-REDUCTION REACTIONS OF IONS WITH MOLECULES 1. Oxidation of Organic Compounds by Variable-Valence Metal Ions 2. Reaction of Variable-Valence Metal Ions with Oxygen, Peroxides, and Quinone s • • • • • . • . CHAPTER XI. REACTIONS OF ATOMS AND RADICALS WITH IONS •• • • • • 1. Reactions of Hydrogen Atom • 2. Reactions of Free Radicals •• CONTENTS 402 427 427 427 428 430 431 432 443 479 479 485 531 531 531
CONTENTSxiCHAPTER XII.REACTIONS OF ION-RADICALSAND561SOLVATED ELECTRONS1.561Reactions of Ion-Radicals2.Solvated Electron561607CHAPTER XIII.IONIC OXIDATION-REDUCTION REACTIONS.1.Methods for Measuring Reaction Ratesfor Electron Transfer from607Ion to Ion2.608Electron Exchange Reactions3.Oxidation-Reduction Reactionsbetween608Ions735LITERATURE CITED(Part Three)
CONTENTS CHAPTER XII. REACTIONS OF ION-RADICALS AND SOLVATED ELECTRONS • 1. Reactions of Ion-Radicals 2. Solvated Electron xi 561 561 561 CHAPTER XIII. IONIC OXIDATION-REDUCTION REACTIONS 607 1. Methods for Measuring Reaction Rates for Electron Transfer from Ion to Ion • • • • • • 2. Electron Exchange Reactions 3. Oxidation-Reduction Reactions between Ions • LITERATURE CITED (Part Three) 607 608 608 735
LISTOFTABLESCHAPTER I.MONOMOLECULAR REACTIONS1Rate Constants for Benzoyl Peroxide17Decomposition2Decomposition of Benzoyl Peroxide18in Various Solvents3Decomposition of Symmetrically19Substituted Benzoyl Peroxides3ADecomposition of UnsymmetricallySubstituted Benzoyl Peroxides21and Phthaloyl Peroxide4Decomposition of Acetyl Peroxide in23Various Solvents5Decomposition of Symmetrical Diacyl24Peroxides,RCOoocOR6Decomposition of Unsymmetrical Diacyl32Peroxides,RicooocOR2357Decomposition of Peroxides,RooR.8Decomposition of Unsymmetrical38Peroxides,Ri00R2409DecompositionofPeroxides,(CH3)3COoCOR.5010Decomposition of Dibasic Peroxides11Decomposition of Hydroperoxides in56Aromatic Solventsxili
LIST OF TABLES CHAPTER I. MONOMOLECULAR REACTIONS 1 2 3 3A 4 5 6 7 8 9 10 11 Rate Constants for Benzoyl Peroxide Decomposition • • • • • • Decomposition of Benzoyl Peroxide in Various Solvents Decomposition of Symmetrically Substituted Benzoyl Peroxides Decomposition of Unsymmetrically Substituted Benzoyl Peroxides and Phthaloyl Peroxide •• Decomposition of Acetyl Peroxide in Various Solvents • • • Decomposition of Symmetrical Diacyl Peroxides, RCOOOCOR Decomposition of Unsymmetrical Diacyl Peroxides, RlCOOOCOR2 •••• Decomposition of Peroxides, ROOR Decomposition of Unsymmetrical Peroxides, RlOOR2 Decomposition of Peroxides, (CH3)3COOCOR • Decomposition of Dibasic Peroxides Decomposition of Hydroperoxides in Aromatic Solvents ••••• xiii 17 18 19 21 23 24 32 35 38 40 50 56
xivLIST.OF TABLES5712Decomposition of Azobisisobutyronitrile1360DecompositionofR-N=N-R1466Decomposition of Ri-N=N-R27015Decomposition at C-C Bond7216Decomposition at N-N Bond17Decomposition of Compounds with74Ruptureof N-C orC-oBond1877Decomposition of Nitrogen Pentoxide1978Decomposition of Nitro Compounds2080Decomposition at C-Metal Bonds.8121Decomposition of xC6HIcl222Constants in Correlation Equations82logk=logko+po23Compensation Effect for Monomolecular83Decomposition Reactions24Volume Change Av+ in Decomposition84ofMolecules25Range of Variation of k forDecomposition of Initiators85in Various SolventsCHAPTER II.BIMOLECULAR ANDTRIMOLECULAR REACTIONS9326Dimerization of Unsaturated Compounds.9427Volume Change in Diels-Alder Reaction9528Reactions of Amines with Peroxides9929Reaction ROOH+R'H->Free RadicalsK30Reactions of Hydroperoxides 2 RooH100Complex_k,Free Radicals
xiv LIST. OF TABLES 12 13 14 15 16 17 18 19 20 21 22 23 24 Decomposition of Azobisisobutyronitrile Decomposition of R- N = N - R Decomposition of Rl - N = N - R2 Decomposition at C - C Bond Decomposition at N - N Bond Decomposition of Compounds with Rupture of N - C or C -0 Bond • Decomposition of Nitrogen Pent oxide Decomposition of Nitro Compounds Decomposition at C-Metal Bonds .•• Decomposition of XC6~IC12 • • • • • ••• Constants in Correlation Equations log k = log ko + pa • • • • Compensation Effect for Monomolecular Decomposition Reactions Volume Change ~V# in Decomposition of Molecules • • • • • 25 Range of Variation of k for Decomposition of Initiators in Various Solvents •••• CHAPTER II. BIMOLECUIAR AND TRIMOLECUIAR REACTIONS 26 Dimerization of Unsaturated Compounds ••• 27 Volume Change in Diels-Alder Reaction 28 Reactions of Amines with Peroxides • • 29 Reaction ROOR + R'R~Free Radicals 30 Reactions of Rydroperoxides 2 ROOR-.-!S. Complex-4Free Radicals • .-:-:- 57 60 66 70 72 74 77 78 80 81 82 83 84 85 93 94 95 99 100