Kondensierte Nitrobenzimidazole

Abstract

Bei der Quecksilber(I1)-EDTA-Dehydrierung von 2-tert. Amino-5-nitroanilinen entstehen unter 4-Elektronenentzug die entsprechenden Benzimidazole. Durch methodische Modifizierungen konnte die Ausbeute im Vergleich zu derjenigen bei Standardbedingungen erhoht werden. Condensed NitrobehzimidazolesDehydrogenation of 2-(tert. amino)-5-nitroanilines with mercury(I1)-EDTA leads to benzimidazoles by withdrawal of four electrons. By modifications of the procedure the yield was improved beyond that obtained under standard conditions.Vor einiger Zeit zeigten wir, daR heterocyclische Anilin-Derivate') grundsatzlich einer Quecksila ber(I1)-EDTA-Dehydrierung zuganglich sind, und Derivate mit ortho-standiger Aminogruppe vom Typ 1 eine Nachbargruppenbeteiligung zu Benzimidazolen') eingehen konnen.The rheological properties and fluid-keeping capacities of artificial vaselins of different compositions were investigated. A mathematical relation was established between the yield point, the thixotropy and the concentration of the solid phase or the isoparaffin contents. +) Herrn Prof. Dr. H. Oelschtuger zum 60. Geburtstag gewidmet 036%233/82/04044339 $ 02.50/0 Q

Synthesis of quinoxaline derivatives from substituted acetanilides through intramolecular quaternization reactions

“…Somewhat related processes, always involving hydrogen-containing nucleophilic groups, are the cyclization of N-(2-chloroethyl)-and N-chloroacetyl-o-phenylenediamines to 1,2,3,4-tetrahydroquinoxalines 31 and the corresponding 2-oxo derivatives, 22,27,32 respectively. In our case the starting materials were the substituted o-phenylenediamines 44-53, which were in turn prepared from 2-fluoro-5nitroanilines 6 and 40 and dimethylamine or cyclic secondary amines (44)(45)(46)(47)(48)(49)(50) or by reduction of N,N-dialkylamino-onitroanilines 41-43 (51-53). Attempts to prepare compound 44 from dimethylamine and 2-chloro-5-nitroaniline 5 failed owing to the low reactivity of the chlorine atom of the latter.…”

“…At room temperature compound 58 also decomposes very quickly to salt 28 in (CD 3 ) 2 SO solutions used for NMR; CDCl (42), 118 (16), 104 (24) and 91 (32). 5), 232 (6), 220 (100), 206 (11), 192 (100), 178 (8), 160 (26), 146 (65), 131 (45), 118 (14), 104 (22) and 91 (16). (7), 146 (32), 131 (12), 117 (21), 104 (12) and 91 (10).…”