Studies in electrocyclic aromatic substitution by the diazo group

Abstract

This Thesis is concerned with the synthesis of 1,2-benzoand 1,2-thienodiazepines by electrocyclic aromatic substitution reactions of the diazo group. The diazoalkenes were produced in aprotic solvent by the thermal decomposition of the sodium salts of the tosylhydrazones of ocß- unsaturated ketones.

The effect of substituents, in the aryl rings, on the product ratio obtained from the decomposition of 2-(diarylmethylene) cyclopentanone tosylhydrazone sodium salts has been examined. The mechanism by which 1,2-benzodiazepines are formed in this reaction is discussed with reference to the effect of substituents and to the results of some deuterium labelling experiments.

The difference in the reactivity of the benzene and thiophene rings to substitution and the effect of steric constraints on the courses of these reactions is discussed.

This Thesis is concerned with the synthesis of 1,2-benzoand 1,2-thienodiazepines by electrocyclic aromatic substitution reactions of the diazo group. The diazoalkenes were produced in aprotic solvent by the thermal decomposition of the sodium salts of the tosylhydrazones of oc,ß-unsaturated ketones.

The effect of substituents, in the aryl rings, on the product ratio obtained from the decomposition of 2-(diarylmethylene) cyclopentanone tosylhydrazone sodium salts has been examined. The mechanism by which 1,2-benzodiazepines are formed in this reaction is discussed with reference to the effect of substituents and to the results of some deuterium labelling experiments.

The difference in the reactivity of the benzene and thiophene rings to substitution and the effect of steric constraints on the courses of these reactions is discussed.