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2‐(4′‐Fluorophenyl)imidazole. Nitration studies
Author(s) -
Amato J. S.,
Grenda V. J.,
Liu T. M. H.,
Grabowski E. J. J.
Publication year - 1979
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570160613
Subject(s) - chemistry , oleum , nitration , nitric acid , yield (engineering) , sulfuric acid , acetic acid , imidazole , reagent , medicinal chemistry , organic chemistry , nitroimidazole , pyrrole , carboxylic acid , metallurgy , materials science
Reactions of 2‐(4′‐fluorophenyl)imidazole ( 1 ) and related compounds under various nitrating conditions are discussed. With 90% nitric acid in 20% oleum at −10°, 1 affords 2‐(4′fluorophenyl)‐4(5)‐nitroimidazole ( 2 ) in 80% yield. Reaction of 2 with the same reagents at 25° affords 2‐(4′‐fluoro‐3′‐nitrophenyl)‐4(5)‐nitroimidazole ( 4 ) in 90% yield, whereas with 90% nitric acid in acetic acid at 95°, 2 affords 4,5‐dinitro‐2‐(4′‐fluorophenyl)imidazole ( 5 ) in 80% yield. Reaction of 1 with 70% nitric acid in concentrated sulfuric acid at 25° affords 2‐(4′‐fluorophenyl)‐5‐hyroximinoimidazolin‐4‐one ( 6 ), which rearranges and hydrolyzes to 5‐(4′‐fluorophenyl)‐1,2,4‐oxadiazole‐3‐carboxylic acid. A discussion of these reactions is presented.