University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Spring 1962 THE EFFECT OF STRUCTURE ON THE BAEYER-VILLIGER OXIDATION OF AROMATIC CYCLOALKANONES MICHAEL G. ISRAEL Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation ISRAEL, MICHAEL G., "THE EFFECT OF STRUCTURE ON THE BAEYER-VILLIGER OXIDATION OF AROMATIC CYCLOALKANONES" (1962). Doctoral Dissertations. 780. https://scholars.unh.edu/dissertation/780 This Dissertation is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. This dissertation has been 62—6520 microfilmed exactly as received ISRAEL, Michael G., 1935- THE EFFECT OF STRUCTURE ON THE BAEYER- VILLIGER OXIDATION OF AROMATIC CYCLO- ALKANONES. U niversity of New H am pshire, Ph.D., 1962 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan THE EFFECT OF STRUCTURE ON THE BA EYE R—VILLIGE R OXIDATION OF AROMATIC CYCLOALKANONES BY MICHAEL G. ISRAEL B. A., Colby College, 1957 A THESIS Submitted to the University of New Hampshire In Partial Fulfillment of The Requirements of the Degree of Doctor of Philosophy Graduate School Department of Chemistry May, 1962 This thesis has been examined and approved. O u r J L O l - {'KQ a k J j .l H h„ J Date ACKNOWLEDGEMENT The author wishes to express his sincere gratitude to Dr. P. R. Jones, under whose direction th is work was performed. He also wishes to thank Dr. Jones for his assistance and guidance during the preparation of this manuscript. "VV\-^cJl>oajL^L (o ■ -I*. S 'loaS L . TABLE OF CONTENTS Page INTRODUCTION ............................................................................................. 1 HISTORICAL .................................................................................................. 3 RESULTS....................................................................................................... 11 I. Preparation of Ketonic StartingMaterials . 11 II. Baeyer—Villiger Oxidation of Ketones ...................... 19 DISCUSSION.................................................................................................. 28 EXPERIMENTAL............................................................................................. 35 I. Preparation of Ketonic Starting Materials . 35 1 . Acenaphthenequinone ............................................... 35 2 . 1 . 2—Diphenylacenaphthene—l, 2—diol .... 36 3. 2, 2*~Diphenylac ana ph then o n e ......................... 38 k- 1 , 2—Dimethylscenaphthene— 1 , 2*~diol .... 37 .. 5. Attempted Preparation of 2,2—Dimethyl— acenaphthenone ............................................................. 37 6. Acenaphthenone by Cyclization of 1—Naphthylacetic A c id .................................. 38 7. I-*Acenaphthenol ................................ 39 8. Acenaphthenone by Oxidation of 1—Acenaphtheno l ................................................ J4.O 9. Attempted Preparation of 5~Methoxy—1— naphthylacetic Acid . ................................. I4.I 10 . c>-Bromoanisole ............................................................ jji 1 1 . 2—(o—Anisyl)— eth y la lc o h o l ......................... Ip2 1 2 . 2—(_o-Anisyl)~ ethylbromide ........ I4.3 13. 'S'—o—Methoxyphenylbutyric A c id ................ )\)\ Ik . ^rMethoxy—l—te tr a lo n e ........................... I4J4. 15. 3, ij.—Dihy d ro~5~-me thoxy— 1—na pht hy 1 acetic A c i d ............................................................................ 55 16. 5—Methoxy—l—naphthy lace tic A c i d ........... lj.6 17. 6--M8 thoxy acenaphthenone ......... I4.7 1 8. o<—Hyd rind o n e ............................................................. 19- 1—Chloromethylnaphthalene ......................... Lj_8 2 0 . JL H 1—Naphthyl)—propionic A c i d ........... ij.9 2 1 . 2 .3—Dihydrophenalone by Cyclization with Aluminum C h lo rid e .................................. 50 22. 2.3—Dihydrophenalone by Cyclization with Hydrogen F lu o r id e ..................................... 51 23. -(2—Naphthyl)—propionic A c i d ........... 52 2k. ■'Benzindanone—3 ............................................ 53 iv Page II. Baeyer'-Villiger Oxidation of Ketones ...................... 55 1. 2 , 2—Diphenylscenaphthenone ....................................... 55 (1) Attempted Oxidation with Permono— sulfuric A cid ............................................................. 55 (2) Attempted Oxidation with Peroxyacetic A c i d ............................................................................... 56 2. General Procedure for use of Trifluoro— peroxy Acetic A cid ........................................................ 56 3 . 2 , 2—Diphenylacenaphthenone ....................................... 57 ij.. Acenaphthenone ................................. 59 5. 6—Methoxya cenaphthenone ..................... 63 6. —Hyd rind o n e ...................................................................... 6If. 7. 2, 3—Dihydrophenalone ..................................................... 66 8. [j., 5*~Benzindanone~”3........................... 68 9. Preparation of 7,8—Benzcoumarin ......................... 69 SUMMARY ......... ................................................................. 71 BIBLIOGRAPHY ............................................................................................. 72 v INTRODUCTION In the course of the Baeyer-Villiger oxidation of a ketone, initial addition of peroxy acid to the carbonyl group forms a hydroxyperoxy ester. This suffers cleavage to form an electron-deficient ion which undergoes rearrangement to an ester or a lactone. The migratory aptitude of groups in the rearrangement is proportional to their capacity for electron release. Thus, in simple ketones, the group with the greater ability to sustain positive charge in the transition state is the one which migrates during heterolysis. The importance of steric effects in controlling the course of the reaction has received considerable attention in the recent literature. In the presence of sufficient steric hindrance, it is found tnat rearrangement occurs in the direction contrary to that predicted by migratory aptitude studies. Therefore, highly hindered ketones provide evidence for complete steric control while the behavior of simple ketones seems to be controlled by electronic factors. The work to be presented here was undertaken in an effort to resolve the existing enigma regarding the relative importance of steric and electronic effects in the Baeyer— Villiger reaction. While aromatic cycloalkanones would seem to possess unique structural features for an investigation of th is type, few recorded examples are available. I t was planned to choose model ketones from th is class of compounds 2 in view of the expected subtle differences in steric and electronic effects. 3 HISTORICAL The oxidation of ketones to the corresponding ester by the use of peracids was first described by Baeyer and Villiger.^ In addition to permonosulfuric acid, which was used in the original investigation, peroxybenzoic, peroxy— acetic, and trifluoroperoxyacetic acids are also commonly employed as oxidizing agents. Evidence for the general applicability of the reaction in a variety of preparative studies has been reported by many investigators and reviewed by H assall . 2 Considerable attention has been directed towards a more satisfactory understanding of the basic mechanistic features of the reaction. The intermediate peroxy ester(I) was proposed by Criegee.^ 0 0|| HCk. .OOCR'. RCR + R! COsH ----------* ^ t -------------------- * RCOsR + R'COsH R R (I) The existence of the intermediate has been confirmed by kinetic studies of the reaction with a variety of ketones. Priess and Soloway^- worked with peroxybenzoic acid and acid catalyst in chloroform while Hawthorne and Emmons used t r i — fluoroperoxyacetic acid and acid catalyst in ethylene chloride k both concluded that the reaction is general acid—catalyzed. The transition state in the rate—determining step must there­ fore be composed of ketone, peroxy acid, and acid catalyst. In the reaction of oxygen—labeled benzophenone with £ peroxybenzoic acid, Doering and Dorfman showed that the cai> bonyl oxygen in the starting ketone becomes the carbonyl oxygen in the resu ltin g ester. The isotopic trac er studies are completely consistent with the proposed mechanism in which the non—equivalence of oxygen atoms is essential. 7 Hawthorne and coworkers' investigated the product distribution obtained in the cleavage of phenyl cyclohexyl ketone with both peroxyacetic acid and trifluoroperoxyacetic acid under the same reaction conditions. The comparison showed that a smaller percentage of phenyl migration occurs in the presence of peroxyacetic acid. In order to account for the difference in selectivity between migrating groups, it was concluded that group migration and acid catalyzed heterolysis of the peroxide bond are concerted. The rate—determining step was established for the reaction of trifluoroperoxyacetic acid with a variety of sub­ stituted acetophenones in ethylene chloride and acetonitrile at 29.8°. Hammett plots of rate data vs. 6 gave negative p—values for both solvents. As generally observed in car­ bonyl additions reactions, one would expect positive