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LD5655.V856 1966.G733.Pdf (6.196Mb) A STUDYOF THE SYNTHESISAND REACTIONS OF NKW POLYNUCLEARAROMATIC ACIDS ANDRELATED COMPOUNDS by . Edward James Greenwood, B.S., M.S. Thesis submitted to the Graduate Faculty of the Virginia Polytechnic Institute in candidacy for the degree of DOCTOROF PHILOSOPHY in Chemistry APPROVED: Chainnan, Dr. F. A. Vingiello Dr. L. K. Brice, Jr. Dr. P. E. Field Dr. J. G. Mason Dr. J. F. Wolfe February, 1966 Blacksburg, Virginia -2- TO PATAND DEBBIE -3- ACKNOWLEDGEMENTS The author wishes to express his sincere and earnest appreciation to Dr. Frank A. Vingiello for his guidance and encouragement throughout the course of this work. Thanks are also extended to the other faculty members and to fellow graduate students for their valuable assistance. Particular appreciation is due to Mr. Thomas Greenwood who performed elemental analyses on six compounds prepared in this work. Financial assistance received in the form of a part-time instructorship from Virginia Polytechnic Institute and a research fellowship from the National Institutes of Health is gratefully acknowledged. Finally, the author wishes to express his appreciation of the help and encouragement provided by his wife which was essential to the successful completion of this work. -4- TABLEOF CONTENTS Page I. INTRODUCTION• • • • • • • • • • • • • • • • • 8 II. NOiwlliNCLATURE• • • • • . 12 III. HISTORICAL . • • • • • 14 IV. DISCUSSIONOF RESULTS. • • • • • • . • • 29 A. Preparation of Starting Materials • • • JO 1. l-Bromo-3-chloronaphthalene • • • • JO 2. 2-(J-Chloro-l-naphthyl- methyl)bromobenzene •••••••• 32 B. The Unequivocal Synthesis of Dibenzo[hi,l]chrysen-9-one •••• • • • 47 1. 2-(J-Chloro-l-naphthylmethyl)- 2'-carboxybenzophenone and 6-chloro-7-(2-carboxyphenyl)- benz[a)anthracene ••. • • • • • • . 47 2. 14-Chlorodibenzo[hi,l]- chrysen-9-one •••.•.••••• 52 J. Dibenzo[hi,l]chrysen-9-one ••••• 56 C. The Synthesis of Naphtho[J,2,1-fg]- naphthacen-9-one ••••••••• • • • 59 1. 2-(3-Chloro-l-naphthylmethyl)- benzophenone and 6-chloro-7- phenylbenz[a]anthracene •• • • • • 59 -5- TABLEOF CONTENTS(Cont.) Page 2. 2-()-Cyano-l-naphthylmethyl)- benzophenone and 6-cyano-7- phenylbenz[a]anthracene •••••• 69 ). Naphtho(),2,1-fg]naphthacen- 9-one •••••••••••• • • • 70 D. The Synthesis of Phenalo[2,),4,5- defg]naphthacene-4,8-quinone ••• • • • 74 E. Infrared Spectral Interpretations • • • 78 F. The Partial Resolution of 7-(2- carboxyphenyl)benz[a]anthracene • • • • 82 v. EXP~RIMENTAL••••••••••••• • • • • 89 VI. SUMMARY.• • • • • • • .' . • • • • • • • • • • 124 VII. APPENDIX • • • • • • • • • • • • • • · • • • • 130 VIII. LITERATUR.I!;CITED • • • • • • • • • ••.•••• 148 IX. VITA •••••• . • • • • • • • • • • • • • 157 -6- TABLEOF SPECTRAIN APPENDIX Infrared Page Spectra 1. 2-{J-Chloro-1-naphthylmethyl)bromobenzene • • • 131 2. 2-Bromophenyl 3-chloro-1-naphthyl ketone •• • • 131 3. 2-Bromophenyl-1-(3-chloronaphthyl)carbinol. • • 132 4. 2-{J-Chloro-1-naphthylmethyl)-2'- carboxybenzophenone • • • • • • • • • • • • • • 132 5. 2-{J-Chloro-1-naphthylmethyl)-2'- carbomethoxybenzophenone • • • • • • • • • • • • 133 6. 6-Chloro-7-(2-carboxyphenyl)- benz[a]anthracene ••••••••••••••• 133 7. 6-Chloro-7-(2-carbomethoxyphenyl)- benz[a]anthracene • • • • • • • • • • • • • • • 134 8. 14-Chlorodibenzo[hi,l]chrysen-9-one •••• • • 134 9. 14-Chloro-9H-dibenzo[hi,l]chrysene ••••• • • 135 10. Dibenzo[hi,l]chrysen-9-one ••••••• • • • • 135 11. 2-{3-Chloro-1-naphthylmethyl)benzophenone • • • 136 12. 6-Chloro-7-phenylbenz[a]anthracene •• • • • • • 136 13. Dibenzo[a,l]pyrene ••••••••••• • • • • 137 14. 2-(3-Cyano-l-naphthylmethyl)benzophenone • • • • 137 15. 6-Cyano-7-phenylbenz[a]anthracene • • • • • • • 138 16. Naphtho[3,2,l-fg]naphthacen-9-one • o • e • • • 138 17. 6-Cyano-7-(2-carboxyphenyl)benz[a]anthracene •• 139 18. Phenalo[2,J,4,5-defg]naphthacene-4,8-quinone • • 139 -7- TABLt OF SP~CTRAIN APPENDIX(Cont.) Ultraviolet-Visible Page Spectra 1. 6-Chloro-7-(2-carboxyphenyl)- benz[a]anthracene • • • • • • • • • • • • • • 140 2. 6-Chloro-7-(2-carbomethoxyphenyl)- benz[a]anthracene • • • • • • • • • • • • • • 140 J. 14-Chlorodibenzo[hi,l]chrysen-9-one • • • • • 141 4. 14-Chlorodibenzo[hi,l]chrysen-9-one • • • • • 141 5. 14-Chloro-9H-dibenzo[hi,l]chrysene. • • • • • 142 6. 14-Chloro-9H-dibenzo[hi,l]chrysene. • • • • • 142 1. Dibenzo[hi,l]chrysen-9-one. • • • • • • • • • 143 s. Dibenzo[hi,l]chrysen-9-one. • • • • • • • • • 143 9. 6-Chloro-7-phenylbenz[a]anthracene •• • • • • 144 10. Dibenzo[a,l]pyrene •••. • •••• • • . .. • • 144 11. 6-Cyano-7-phenylbenz[a]anthracene • • • • • • 145 12. Naphtho[J,2,l-fg]naphthacen-9-one • • • • • • 145 13. Naphtho[J,2,l-fg]naphthacen-9-one . 146 14. 6-Cyano-7-(2-carboxyphenyl)- benz[a]anthracene • • • • • • • • • • • • • • 146 15. Phenalo[2,3,4,5-defg]naphthacene- 4,8-quinone • • • • • • • • • • • •••••• 147 16. Phenalo[2,J,4,5-defg]naphthacene- 4,$-quinone 0 8 0 0 8 I I 8 I • I • .. • .. 8 .• 147 -8- INTRODUCTION -9- INTRODUCTION It is now well established that many polynuclear aromatic compounds possess a measurable degree of physiological activity. However, only limited deductions have been made regarding the correlation of molecular structure with degree of biological activity. This is complicated by the fact that certain polycyclic systems substituted with different groups show extreme differences in biological activity, i.e., 7,12-dimethylbenz[a]- anthracene1 is a potent carcinogen, and 7-phenylbenz[a]- anthracene 2 is an anti-tumor agent. In order to gain further insight into the relation of structure and mechanism of physiological activity, a significant amount of work has been done on the synthesis of polynuclear aromatic compounds to be used for biological testing. At the same time much has been learned about the unique chemical properties of these compounds and the study of· their synthesis has made a definite contribution to the field of organic chemistry. Recently, in This Laboratory 3 , this author synthesized 7-(2-carboxyphenyl)benz[a]anthracene (1) * *This compound, NSC #76322, has recently been tested and has shown activity against Sarcoma-180.4 -10- which underwent cyclodehydration to give either dibenzo[hi,l]chrysen-9-one (2) or naphtho[J,2,l-fg]- naphthacen-9-one (l) on treatment with polyphosphoric acid. Only one product was recovered and was assigned > 2 1 l structure~ on the basis of infrared spectra studies and consideration of electron localization energies and electron densities of the two possible sites of cycliza- tion. -11- The purpose of this investi~ation is to unequiv- ocally synthesize compounds 2 and land conclusively establish which product resulted from the acid 1. These syntheses as well as that of phenalo[2,J,4,5- defg]naphthacene-4,8-quinone (i) will be discusJed in detail in this dissertation and interesting results and conclusions will be presented. It can be speculated that the acid 1 should behave as other optically active biphenyl compounds with bulky substituents in the positions ortho to the pivot 5 6 bond. ' The resolution of the acid into its enantiomers was studied and a discussion of this will be presented. -12- NOMENCLATURE -1)- NOMENCLATURE The nomenclature presented throughout this thesis is in accordance with the "Definitive Rules for Nomenclature" set forth in the Journal of the American Chemical Society, 82, 5545 (1960). For example: 2 12 1 ) 2 4 3· 10 9 9 g 7 6 Benz[a]anthracene Chrysene 8 10 11 12 l 9 2 6 g ) 5 7 6 5 4 4 ) Naphthacene Phenalone In this thesis, all rings are aromatic unless otherwise specified. -14- HISTORICAL -15- HISTORICAL Cancer has been known to man for centuries. The first indication that cancer could be due to external 7 factors came in 1775 when Pott observed that a high percentage of chimney sweeps exposed to soot developed scrotal cancer. It was not until 1915 that Yamagiwa and Ichikawa 8 first induced skin tumors in animal~· using coal tar. With the synthesis and testing of . dibenz[a,h]anthracene, Kennaway9 and associates in 1932 first demonstrated that cancer could be induced in animals by a pure chemical. Further experimentation 10 by Cook and Kennaway indicated that many of the more potent carcinogens consist of the benz[a]anthracene ring system with alkyl substituents at either the 7,8,9, or 12 positions. Rea~ons for the high degree of carcinogenicity of these compounds have been attributed in part to the electronic effect 11 of the alkyl substituents, and to their close structural resemblance to steroids. Conversely to the fonner, 12 Badger has found that both electron repelling (methyl) and electron attracting (cyano) groups increase the carcinogenic activity of benz[a]anthracene. -16- In recent years, there has been a renewal and inten- sification of interest in the study of carcinogenesis. Despite the tremendous effort put forth, all attempts to correlate biological activity with chemical structure have met with only limited success. This is due to the fact that the exact mechanism of carcinogenesis remains a mystery. Many polycyclic aromatic compounds have been found to be tumor inhibiting (carcinostatic) 13 or tumor re d ucing. ( carcino. l ytic. ) • 2,J One such compound is the aromatic acid 1, mentioned in the Introduction. Being an analog of an optically active biphenyl, it exists as a racemate of two optically active forms. It has been observed that the biological activity of a racemic mixture is greatly altered by its resolution into 14 optically active forms. In many cases, one enantiomer was found to be very active while the other isomer was relatively inactive. The acid 1 was partially
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