88061-85-2Relevant academic research and scientific papers
Unusual Synthesis of Stable Pyridinium Dinitromethylides
Andreasson, Eva,Newton, Christopher G.,Ollis, W. David,Rees, Charles W.,Smith, David I.,Wright, Derek E.
, p. 816 - 817 (1983)
Nitration of the imidazopyridines (1) or (2), (5) or (6), and (9) with nitric and sulphuric acids gives the pyridinium dinitromethylides (4a), (8), and (10), respectively, in which the pyridinium and dinitromethylide groups are orthogonal.
peri-Substituted Imidazopyridines. A New Reductive Elimination Reaction
Rees, Charles W.,Smith, David I.
, p. 1159 - 1164 (2007/10/02)
A new reductive elimination reaction of 3,5-disubstituted imidazopyridines (3) with hydrazine is reported.Thus on treatment of the 3,5-dibromo (7a), 5-bromo-3-nitro (7b), and 3,5-dinitro (4) derivatives with hydrazine hydrate in hot ethanol, the bromine and nitro groups are replaced by hydrogen.A mechanism based on the conjugated relationship of these peri-substituents is proposed and used to explain the reported conversion of 1,3,5-trichloro-2,4,6-trinitrobenzene (9) into 1,3-dichloro-4,6-dinitrobenzene (10).A variety of other 3-nitro-5-substituted imidazopyridines (15)-(18) is described, but these could not be cyclised to 1,2,4-triazacyclopentindenes.The 3-amino-5-methoxycarbonyl derivative (19a) cyclises to the triazacyclopentindenone (20) with sodium methoxide.
