Several mixed benzils containing one substituent in the benzene ring have been prepared, and their reaction iith various ':etonic reagents considered. In addition the absorption spectra of these benzils have been recorded.
p -Nitro acetylbenzoin and p- nitrobenzil have been prepared by a greatly improved method.
Tvo methods for the determination of the structure of ketonic derivatives of benzils have been described and the structure of p- nethoxybenzil hydrazone determined.
The action of potash and of alcoholic potassium cyanide on the benzils has been described.
The mixed 'oenzoin. condensation has been discussed v ith the aid of a diagram and the importance of quantitative uor:- in this connection is emphasised.
The reactivity of the mixed benzils eras con- sidered, and i t vins seen that though the effect of the reagent employed vas very important, in many cases it teas found that only one ketonic group reacted.
It z;as sho1n that the main band in the spect um of benzil is probably intimately connected z',ith the effect of substituents on the reactivity of the carbo yl. The spectra of the benzils :,,ere found to shove conside able shifts due to the substituents.
The feasibility of chemical and of physical methods for the determination of the reactivity of a carbonyl groin: has been co_ZE idered, and it has been shown that different methods give different values for the reactivity.
The lack of accurate auantitati ve data obtained under comparable conditions was felt in almos every phase of this work.
It was conclusively shown that the only reage which gave parallel results for all the benzils, was dinitrophenylhydrazine, and that in conseoue,nce it is the most suitable reagent for the characterisation of carbonyl compounds.