Studies on Tropolones

Steel, Derek K. V (1953) Studies on Tropolones. PhD thesis, University of Glasgow.

Abstract

Nitration of tropolone yields a mixture of alpha- and gamma-mononitrotropolones which are oriented by isomerisation, via their methyl ethers, to o- and p-nitrobenzoic acids respectively. Of the derived amino-tropolones the gamma-isomer is also produced by reduction of tropolone coupling-products and is convertible into gamma-hydroxy-, gamma-halogeno-and gamma-cyanotropolone: it also undergoes the Skraup reaction. On the other hand, diazotisation of alpha-amino-tropolone yields much salicylic acid. Nitration of alpha-bromotropolone yields the gamma-nitro-derivative. gamma-Cyanotropolone is used to prepare gamma-carboxy-tropolone and gamma-aminomethyltropolone. alpha-Carboxytropolone is synthesised via a condensate of pimelic and oxalic esters. This condensate is proved by its reactions to be 1:4-dicarbethoxycyclohepta-2:3-dione and on bromination-debydrobromination, it affords alphaalpha'-dibromotropolone. The conversion of tropolones into chlorotropones is described and halogen mobility in these compounds and in halogenotropolones is examined with especial reference to mercaptide reagents which, in most cases, can exhaustively replace the halogen substituents. Some incidental rearrangements are noted. The Interaction of ethyl oxalate and di-beta-cyanoethyl sulphide - examined in course of preliminary experiments on the synthesis of heterocyclic analogues of tropolone - leads to a sulphur-free compound which is identified, by hydrolysis and degradation, as 3:6-dicyanocatechol.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Organic chemistry
• Date of Award: 1953
• Depositing User: Enlighten Team
• Unique ID: glathesis:1953-79102
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 11:42
• Last Modified: 05 Mar 2020 11:42
• URI: https://theses.gla.ac.uk/id/eprint/79102