Abstract:
The Introducti on deals mainly with hi storical studies
on aryne chemi stry and ring closure via arynes , hydride replacement
from aromatic rings by nucleophi les, c l eavage of anthr
aquinones in basic medium and the Leuckart reaction .
This work can be divided into two main s ect i ons.
Section I is concerned with the investigation of t he reaction
of some aromatic ni t ro-compounds with potassamide in l iquid
ammonia. 3-Amino-4- nitrobenzophenone was obtained from the
reacti on of 4-nitrobenzophenone with t his reagent, toge t her
with benzoic acid formed in a competing Haller-Bauer reaction.
Nitrobenzene under these conditions gave a complex
mixture from which 2-phenylphenol was isolated; a reaction
i nvolving benzyne may be i nvo l ved.
4-Nitrodiphenyl sulfone gave 4-aminodiphenyl sulfone
and 4-nitroani l ine. 4-Ethoxydiphenyl sulfone and 4-ethoxynitrobenzene
were isolated when ethanol was used as a co-solvent
in the reaction.
Oxidative coupling reactions were observed with nitrotoluenes.
4-Nitrotoluene gave 4,4t-dinitrobibenzyl which i n a
pro longed reaction gave 4,4t-dinitros t ilbene . 2-Nitrotoluene
gave 2 , 2 t-dinitrobibenzyl, but not the corresponding stilbene
derivative even after a longer time . A rather i nteresting
result was obtained with 1-nitro-2,4,6- trimethylbenzene which
gave a stilbene derivative only. Also the corresponding stilbene
was obtained from bis-(4-nitrophenyl)-methane in a rather slow
r eaction with this reagent .
Section II deals wi th (i) the preparation of 5-chloro-
1-N-methyl aminoanthraquinone and a new synthesis of N-methyl acridones
and (ii) treatment of chloro-anthraquinones with
fo rmamide and a new synthesis of chloro-anthracenes .
5-Chloro-1 -N-methylaminoanthraqui none was synthesised
f rom 1,5-dichloroanthraquinone by treatment with N-methylformamide.
Treatment of 5-chloro-1-N-methylaminoanthraquinone
with potassamide in liquid ammonia or with potassium t-butoxide
i n t-butylbenzene gave N-methylacridone-1-carboxylic acid.
This pleasing result, t he outcome of r i ng opening and alter native
ring closure, is being extended to related ring systems.
