Studies in the Heterocyclic and Carbocyclic Series

Hunter, Leon (1953) Studies in the Heterocyclic and Carbocyclic Series. PhD thesis, University of Glasgow.

Abstract

PART I. Catalytic hydrogenation of 2-9'-fluorenyloyclohexanone, prepared by the reaction of 9-bromofluorene and the sodio-derivative of ethyl cyclohexanone carhoxylate and decarbeth-oxylation of the product, has resulted in the isolation of two stereoisomeric alcohols, cis- and trans-2-9' -fluorenyl-cyclohexanol, and a hexahydride of one of these. Both carbinols yield the same product on dehydration with phosphoric acid. The structure of this product is established as 9-cyclo-Delta1-enylfluorene by the following series of steps microhydrogenation and double bond estimation with perphth-alic acid indicate the presence of one double bond, as does the isolation of an epoxide from the perphthalic acid oxidation and a dihydroxy-derivative via the osmium tetroxide-pyridine complex; the position of the double bond is established by the formation of the same product by the dehydration of 1-9'-fluorenylcyclohexanol; The possible alternative structure of cyclohexylidenefluorene (formed by double-bond migration) is excluded by the fact that this compound, prepared by the dehydration of 9-cyclohexylfluoren-9-ol, is distinct from the product. The absorption spectra of these various dehydration products and their hydrogenation product 9-cyclohexylfluorene, have been recorded and shown to be in accord with the structures variously assigned to them. This work extends and corrects that of Hurd and Mold who isolated one alcohol from the hydrogenation of 2-9'-fluorenylcyelohexanone and regarded its dehydration product as 1:9-cyclohexylenefluorene. PART II. The maleic anhydride adduct with 9:10-diphenyianthracene has been prepared (a) according to the procedure of Bachmann and Kloetzel by refluxing the hydrocarbon in xylene with a thirty mole excess of maleic anhydride, and (b) according to the procedure of Dufraisse, Velluz and Velluz by fusing equal weights of the same two reactants. The adducts are shown to be identical by comparison of their melting points and absorption spectra, and by comparison of three derivatives, their diethyl esters, their dimethyl esters and the trans-dimethyl esters obtained by isomerisation. The suggestion of Dufraisse, Velluz and Velluz that the widely different melting points recorded for the adduct prepared by the two methods are due merely to the different procedures adopted in taking the melting points has been experimentally confirmed. The absorption spectra are in agreement with that recorded for the Dufraisse adduct by Gillet who demonstrated that its similarity to the absorption spectrum of 1:4-diphenyl-naphthalene indicated that 1:4-addition of maleic anhydride had taken place instead of the 9:10-addition, normal with other anthracene derivatives. Chemical confirmation of Glllet's structure for the adduct has now been obtained by an estimation with perphthal-ic acid which showed the presence of an ethylenic double bond and by the characterisation of the epoxides prepared by per-phthalie acid oxidation of the diethyl and dimethyl esters of the adduct. No pure products could be isolated when permanganate oxidation and ozonisation were used similarly to attack the isolated double bond. PART III. The structure of the product of the reaction of o-nitro-aniline with 1-naphthylamine, first prepared by Wohl and Lange and described by them as an "amino-naphthophenazine" without assigning it any definite structure, has been established as 5-amino-ang-benzophenazine and not 7-amino-5:12-diazanaphthacene as suggested by Allen and Webster. Deamination to ang-benzophenazine shows the compound to possess that ring system and not the ring system of lin-benzopnen-azine (i. e. 5:12-diazanaphthacene). Comparison (absorption spectrum and melting point) with an authentic sample of 5-amino-ang-benzophenazine shows that the two compounds are identical. PART IV. The Friedel-Crafts reaction of quinolinic anhydride with naphthalene has been thoroughly investigated and found to give poor results under all the experimental conditions which were tried. Two products were isolated; beta-naphthoyl-picolinic acid, so designated because it has a melting point in agreement with that recorded by Jephcott for the compound which he proved to have this structure and which he prepared by a similar Friedel-Crafts reaction, and alpha-naphthoylpicolinic acid whose structure was proved by potassium hydroxide fusion and by a positive Skraup test for a picolinic acid. Numerous attempts to cyclise this alpha-naphthoylpieolinic acid or its zinc dust and ammonia reduction product, beta-naphthylmethylpicolinie acid, using a wide variety of cyclising agents have all proved unsuccessful. From the few examples present in the literature of cyclisations in which the carboxyl group is attached to the nitrogen ring, evidence is adduced in support of the claim that compounds containing a carboxyl group in the alpha-position to the ring nitrogen atom are peculiarly difficult to cyclise and a possible explanation for this phenomenon is suggested.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Organic chemistry
• Date of Award: 1953
• Depositing User: Enlighten Team
• Unique ID: glathesis:1953-79124
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 11:41
• Last Modified: 05 Mar 2020 11:41
• URI: https://theses.gla.ac.uk/id/eprint/79124