This dissertation has been microfilmed exactly as received Mic 60-6372 HELLING, John Frederic. THE CHEMISTRY OF SOME NEW FUNCTIONAL DERIVATIVES OF FERROCENE. The Ohio State University, Ph.D., 1960 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan THE CHEMISTRY OF SOME NEW FUNCTIONAL DERIVATIVES OF FERROCENE DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The ( M o State University By JOHN FREDERIC HELLING, B.A. ****** The Ohio State University I960 Approved by Adviser Department of Chemistry ACKNOWLEDGMENT The intellectual stimulation and the guidance of Dr. Harold Shechter during this investigation are gratefully acknowledged. His imaginative ideas challenge the unknown; his enthusiasm is infectious. Translations of several Russian papers have been generously pro­ vided by Dr. Kenneth Rinehart, Jr., of the University of Illinois and Dr. Marvin Rausch of the Monsanto Chemical Company. Thanks go to Dr. A. C. Haven, Jr., Dr. S. N. Boyd, and Dr. J. D. Brady of E. I. du Pont de Nemours for gifts of ferrocene. I am grateful for fellowships supported by the National Science Foundation and E. I. du Pont de Nemours. The opportunity to serve as DuPont Teaching Fellow has been of inestimable value to me in develop­ ing a better understanding of chemistry. ii TABLE OF CONTENTS Page I. SUMMARY.......... .......................... 1 II. BACKGROUND.......................................... 3 III. DISCUSSION OF RESULTS................................. 8 A. Nitroferrocene......................... 8 B. Haloferrocene............. ...................... 15 IV. EXPERIMENTAL........................... ............... 23 A. General Information............. 23 B. Synthesis and Reactions of Nitroferrocene.............. 23 Nitroferrocene............................. 23 Catalytic Reduction of Nitroferrocene ....... 2$ Lithium Aluminum hydride Reduction of Nitroferrocene................................ 26 C. Unsuccessful Routes to Nitroferrocene. 27 Reaction of FerrocenyUithium and Amyl Nitrate ......... 27 Sodium Nitrocyclopentadienide......... 28 Reaction of Sodium Nitrocyclopentadienide and Ferrous I o n ................................. 28 Acetylferrocene .................. 29 Reaction of Acetylferrocene and Ifydrazoic A c i d ......... ........................ 29 O-Benzylhydroxylaraine.......... 30 AnrLnof erroc en e ......... .. 30 Oxidation of Aminoferrocene . ...................30 iii TABLE OF CONTENTS (CONTD.) Page IV. EXPERIMENTAL (CONTD.) D. Synthesis and Reactions of Haloferrocenes ........... 31 Chloromercuriferrocene ..... ................ 31 Iodoferrocene ............... .......... 32 _ Ferrocenylboronic Acid and 1,1’- Ferrocenylenediboronic Acid ....... ....... 33 Bromoferrocene................................... 3h Chloroferrocene .......... 35 1,1*- Dibromoferrocene .................. 35 Ferrocenylmagnesium Bromide (Methyl Iodide as Entrainer) .................. 35 Ferrocenylmagnesium Bromide (Trace Amount of Methyl I o d i d e ) ............................... 37 Ferrocenylmagnesium Iodide (Methyl Iodide as Entrainer)....................... 37 Ferrocenylmagnesium Iodide (Trace Amount of Methyl I o d i d e ) ............................... 38 Ferrocenylmagnesium Chloride...................... 38 Attempted Reaction of Bromoferrocene and Methylmagnesium Iodide........................ 39 Reaction of Ferrocenylmagnesium Bromide and Cobaltous Chloride ................ ..... 39 Reaction of 1,1’- Dibromoferrocene with Magnesium ......... HO Coupling of Iodoferrocene with Magnesium........... k2 Reaction of Iodoferrocene and Butyllithium ..... U3 Reaction of Iodoferrocene and Sodium Amide.......... U3 Reaction of Ferrocenylmagnesium Bromide and Amyl Nitrate....................... Uit. iv TABLE OF CONTENTS (CONTD.) Page IV. EXPERIMENTAL (CONTD.) E. Miscellaneous Preliminary Results.................. Reaction of Ferrocenyllithium and Acetone Cyanohydrin Ni t r a t e .......................... 1|5 Reaction of Ferrocenylmagnesitim Bromide and DinitrogenTetroxide .................... U6 APPENDIX ......... ... .................................... U7 AUTOBIOGRAPHY................................................SO v LIST OF TABLES Table Page I. Reactions of Haloferrocenes and Magnesium............... 17 LIST OF FIGURES Figure Page I. Infrared Spectrum of Nitroferrocene........... U8 II. Ultraviolet Spectrum of Nitroferrocene................. U9 vi I. SUMMARY Nitroferrocene was prepared in 2% conversion by addition of dinitrogen tetroxide in ethyl ether at -70° to ferrocenyllithium in ethyl ether at -70°. The structure was established by catalytic hydro­ genation to aminoferrocene with Raney nickel as catalyst. Reduction of nitroferrocene with lithium aluminum hydride gave aminoferrocene and azoferrocene. No ferrocene derivatives were isolated from reaction of ferro- cenyllithium and amyl nitrate. Reaction of ferrocenyllithium and acetone cyanohydrin nitrate gave cyanoferrocene and several unidenti­ fied ferrocene derivatives. Nitroferrocene was not detected. Oxidation of aminoferrocene with peroxytrifluoroacetic acid caused the destruction of the ferrocene nucleus. Reaction of ferrous ion and nitrocyclopentadienide ion did not produce 1,1'- dinitroferrocene. Grignard reagents were prepared by controlled reactions of magnesium with chloroferrocene, bromoferrocene, iodoferrocene, and 1,1'- dibromoferrocene, respectively, in tetrahydrofuran. Effective techniques involving methyl iodide and ethylene bromide have been developed. Ferrocenyl Grignard reagents decompose at elevated temper­ atures to give ferrocene and biferrocenyl. Ferrocenylmagnesium bromide reacts with cobaltous chloride to give biferrocenyl in 80# conversion. These coupling and reduction reactions may be attributed to ferrocenyl radicals. Similarly, butyllithium reacts with iodoferrocene to give ferro- 1 cene and biferrocenyl, in addition to ferrocenyllithium. Reaction of iodoferrocene and sodium amide in liquid ammonia yields azoferro­ cene. Reaction of acetylferrocene and hydrazoic acid in trichloroacetic acid containing a trace of sulfuric acid produced nearly the theoretical amount of nitrogen hut no ferrocene derivative remained. Helds of ferrocenylboronic acid and 1,1*- ferrocenylenediboronic acid from the published reaction of ferrocenyllithium and butyl borate have been increased considerably by use of ethyl ether- tetrahydrofuran as a solvent for preparation of ferrocenyllithium. The known reaction of ehloromercuriferrocene and iodine is better performed in methylene chloride rather than in hot xylene as previously reported. II. BACKGROUND The unexpected discovery that biscyclopentadienyl iron (l, 2), (1) T. J. Kealy and P. L. Pauson, Nature, 168, 1039 (l95l). (2) S. A. Miller, J. A. Tebboth, and J. F. Tremaine, J. Chem. Soc., 632 (1952). ferrocene, possesses aromatic character (3) has prompted many chemists (3) R. B. Woodward, M. Rosenblum, and M. C. Whiting, J. Am. Chem. Soc., 7U, 3H58 (1952). to undertake extensive investigations of its properties. Initially it was found that in spite of its formal unsaturation, ferrocene would not undergo BLels-Alder addition to maleic anhydride and could not be hydrogenated under conditions usually satisfactory for catalytic hydro­ genation of olefins (3). Furthermore, the unusual thermal stability of ferrocene, the presence of a single C-H stretching frequency in its infrared spectrum (U), and a number of other physical measure- (U) G. Wilkinson, M. Rosenblum, M. C. Whiting, and R. B. Woodward, J. Am. Chem. Soc., 7U, 2125 (195U). raents (5) suggested the now-familiar sandwich structure (U). The (5) For the most recent and informative review of the chemistry of metallocenes see A. N. Nesmeyanov and E. G. Perevalova, Uspekhi Khimii, 27, 3 (1958). equivalence of carbon atoms in ferrocene and the presence of six 3 delocalized, electrons in each ring bear a striking resemblance to benzene. Early experiments showed that ferrocene could be acylated under typical Friedel-Crafts conditions (3). Since then ferrocene has been found to 'undergo numerous substitution reactions similar to those of benzene. In ease of electrophilic substitution ferrocene surpasses anisole (6). (6) P. L. Pauson, Quart. Rev., 9j 391 (1955). In contrast to benzene, ferrocene cannot be nitrated or halo- genated directly and cannot be sulfonated in concentrated sulfuric acid. Halogens, nitric acid, and sulfuric acid oxidize ferrocene to the ferricinium cation (3)* a stable species which does not undergo electrophilic substitution. When warned with bromine in carbon tetra­ chloride, ferrocene is converted to pentabromocyclopentane (7). (7) A. N. Nesmeyanov, E. G, Perevalova, and 0. A. Nesmeyanova, DolcLady Akad. Nauk SSSR, 100, 1099 (1955). Chlorine effects cleavage at room temperature to give pentachlorocyclo- pentane (7). Iodine forms an adduct with ferrocene, FeCC^H^^’lO I2, which, in water, produces the ferricinium ion (7). As a result of the sensitivity of ferrocene to oxidation, many of its derivatives must be prepared by indirect routes. The most important intermediates in these synthetic paths result from metalla- 5 tion of ferrocene with butyllithium (8, 9), phenyls odium (10), (8) R. A. Benkeser, D. Goggin, and G. Schroll, J. Am. Chem. Soc., 76, 1*025 (195U). (9) A. N. Nesmeyanov, E. G. Perevalova, R. 7. Golovnya* and 0. A. Nesmeyanova, Doklady Akad. Nauk SSSR, 97 , 1*59 (1951*). (10) A. N. Nesmeyanov, E. G. Perevalova, and Z. A. Beinoravichute, Doklady Akad. Nauk