ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Syntheses of Sulfonated Derivatives of 2-FluoroanilineSynthesis of 4-amino-3-fluorobenzenesulfonic acid (3) was achieved in two ways: reaction of 2-fluoroaniline (1) with amidosulfonic acid and by first conventionally converting 4-nitro-3-fluoroaniline (8) to 4-nitro-3-fluorobenzenesulfonyl chloride (9) followed subsequently by hydrolysis to 3-fluoro-4-nitrobenzenesulfonic acid (10) and reduction. Hydrogenolysis of 3 gave sulfanilic acid (7). Both, sulfonation of fluorobenzene (6) to 4-fluorobenzenesulfonic acid (11) followed by nitration and sulfonation of 1-fluoro-2-nitrobenzene (12) led to 4-fluoro-3-nitrobenzenesulfonic acid (13). Reduction of 13 gave the isomeric 3-amino-4-fluorobenzenesulfonic acid (4), which was also obtained both by sulfonation of 1 and by sulfonation of o-fluoroacetanilide (14) followed by hydrolysis. Selective hydrogenolyses of 2-amino-5-bromo-3-fluorobenzenesulfonic acid (15), prepared by reaction of 4-bromo-2-fluoroaniline (16) with amidosulfonic acid, and of 4-amino-2-bromo-5-fluorobenzenesulfonic acid (20), obtained by sulfonation of 5-bromo-2-fluoroaniline (19) yielded the isomers 2-amino-3-fluorobenzenesulfonic acid (5) and 3, respectively. The fourth isomer, 3-amino-2-fluorobenzenesulfonic acid (2), was synthesized by sulfur dioxide treatment of the diazonium chloride derived from 2-fluoro-3-nitroaniline (21) to 2-fluoro-3-nitrobenzenesulfonyl chloride (22), followed by hydrolysis to 2-fluoro-3-nitrobenzenesulfonic acid (23) and final Béchamp-reduction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19830660108
