3-Nitrosalicylic acid → HCID 178522675, compound

Anhydrous 5-aminotetrazole (15 g) and phosphorus trichloride (6 ml) were added to a suspension of 3-nitrosalicylic acid (16 g) in dry benzene (250 ml). The mixture was stirred and heated at reflux for 20 hours. The mixture was then cooled and diluted with petroleum ether (b.p. 60°-80° C.; 250 ml) and the resulting solid was filtered off. The solid was treated with dilute hydrochloric acid (200 ml; 2N) and the mixture was stirred for 30 minutes, and the solid was then filtered off and washed with ethanol and dissolved in aqueous ammonia solution (2N). This solution was treated with decolourizing charcoal and filtered and the filtrate was acidified by treatment with concentrated hydrochloric acid to give 2-hydroxy-3-nitro-N-(tetrazol-5-yl)benzamide (5.0 g), m.p. 236°-238° C. (with decomposition).

1. temperatureheated
2. temperatureat reflux for 20 hours
3. temperatureThe mixture was then cooled
4. filtrationthe resulting solid was filtered off
5. additionThe solid was treated with dilute hydrochloric acid (200 ml; 2N)
6. stirringthe mixture was stirred for 30 minutes
7. filtrationthe solid was then filtered off
8. washwashed with ethanol
9. dissolutiondissolved in aqueous ammonia solution (2N)
10. additionThis solution was treated with decolourizing charcoal
11. filtrationfiltered

ORD record

ord-a9dcdf6196424e3e89bfe337c9b1ab7f

Source dataset

uspto-grants-1979_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04146631