Substituent Interactions in Ortho-Substituted Nitrobenzenes

Sword, Ian Pollock (1967) Substituent Interactions in Ortho-Substituted Nitrobenzenes. PhD thesis, University of Glasgow.

Abstract

A review is given of relevant interactions published in the literature between 1964 and 1967. Degradative studies show that the product obtained by treatment of 2,3-epoxy-3-(o-nitrophenyl)propiophenone with ethereal hydrogen chloride is 6-chloro-1,4-dihydro-1,3-dihydroxy-2-phenyl-4-oxoquinoline, and that the corresponding unhalogenated heterocycle is the product when quinol is present in the reaction mixture. 3-Carbamoylanthranil is the sole crystalline product from the reaction of o-nitrobenzyl cyanide with concentrated sulphuric acid, and evidence is presented that o-nitrophenylacetamide is not an intermediate in the cyclisation. Whereas 5-hydroxy-2-nitrobenzaldehyde and phenol are shown to react in ethereal hydrogen chloride to give the expected halogenated. product, namely 7-chloro-5-hydroxy-3-(p-hydroxyphenyl)anthranil, 5-methoxy-2-nitro-benzaldehyde gives, abnormally, the corresponding unhalogenated anthranil. The latter reaction is discussed in the light of a working hypothesis regarding possible mechanisms involved. The scope of the reaction of o-nitrobenzylidene derivatives with aqueous ethanolic potassium cyanide is explored and extended. The plethora of products so obtained are shown by degradative, synthetic and spectroscopic studies to be derivatives of quinoline N-oxide and of 1-hydroxyindole. Unexpectedly, in some instances a 4-cyano substituent in the quinoline-type products fails to survive the reaction without hydrolysis. This is discussed with reference to the isolation of 4-acetyl-5-methyl-3-(p-nitrophenyl)-2-aminofuran from reaction of p-nitrobenzylideneacetylacetone with aqueous ethanolic potassium cyanide. The Michael addition product from o-nitrobenzyl cyanide and 1,2-di-benzoylethylene is synthesised; its reactions with sodium ethoxide and sodium carbonate are investigated and shown to give products comparable with those from the reactions of o-nitrobenzylidene derivatives described above.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Organic chemistry
• Date of Award: 1967
• Depositing User: Enlighten Team
• Unique ID: glathesis:1967-78448
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 30 Jan 2020 15:22
• Last Modified: 30 Jan 2020 15:22
• URI: https://theses.gla.ac.uk/id/eprint/78448