Labelled compounds of interest as antitumour agents - VI 1. Isotopically efficient syntheses of [15N]-nitrothiophenecarboxamides

✍ Scribed by Anne E. Shinkwin; Michael D. Threadgill

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: French
• Weight: 292 KB
• Volume: 38
• Category: Article
• ISSN: 0022-2135
• DOI: 10.1002/(sici)1099-1344(199611)38:11<1015::aid-jlcr917>3.0.co;2-6

✦ Synopsis

Reaction of 3-cyanothiophene with one equivalent of potassium nitrate in concentrated sulphuric acid causes nitration, concurrent with hydrolysis of the nitrile, to give 5-nitrothiophene-3-carboxamide in high yield. Similarly, 2-cyanothiophene gives 4-nitrothiophene-2-carboxamide and 5-nitrothiophene-2-carboxamide, benzonitrile gives 3nitrobenzamide and 4-methylbenzonitrile gives 4-methyI-3-nitrobenzamide. Extension of this process to use of potassium ['%]-nitrate, formed fiom ['%]-nitric acid (95% isotopic enrichment), enables preparation of the corresponding ['5N]-nitrothiophenecarboxamides in high isotopic yield.