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Anils phenanthridines from

X-ray crystal structure, 6, 516 Benzophenanthridines synthesis from anils, 2, 416 Benzophenanthridines, tetrahydro-synthesis, 2, 469 Benzo[c]phenanthridines synthesis, 2, 414 from aryl isocyanides, 2, 411 from benzynes, 2, 432 Benzo[i]phenanthridines synthesis, 2, 414 Benzophenanthridinones... [Pg.550]

Certain aromatic imines undergo a similar cyclodehydrogenation to the phenanthridine. Benzylideneaniline (330) yields phenanthridine (331) only in sulfuric acid,355 whereas diphenylmethyleneaniline cyclizes in the presence of oxygen or iodine.356 Cyclizations have also been reported in Schiff s bases formed from a- and /J-naphthylamine357 and from 4-aminoquinoline,358 and in the mesomeric betaine 4,5-diphenyl-2-mercapto-l,3,4-thiadiazolium hydroxide.359 Irradiation of the anil of 2-aminonaphthalene (332) in ethanol, however, leads to incorporation of ethanol and the formation of 3-phenylbenzo[/]-quinoline (333).860 Additional photoproducts are obtained when the photolysis is carried out in w-hexanol.361... [Pg.95]

In the simplest case, the conversion of benzylideneaniline to phenanthridine, ring closure occurs satisfactorily in sulfuric acid,151 and both 6-methyl- and 3,6-dimethylphenanthridine have been prepared in the same way, albeit in low yield, from the appropriate acetophenone anil.152 However, Mallory and Woods153 have shown that no phenanthridine is formed when benzylideneaniline is irradiated in either cyclohexane, benzene, or ethanol at 30°-40°, and have ascribed this to the short half-life (ca. 1 second at room temperature154, 155) of the cis isomer [although a successful cyclization has been reported in the case of the dimethylamino derivative (112b)156]. [Pg.348]

The iV-methylamine (160) (R = Me) gives a complex mixture of products when treated under the same conditions.186 It was shown subsequently that prior reduction of the anils used as starting materials is, in fact, unnecessary since in the presence of potassamide in liquid ammonia (o-chlorobenzylidene)aniline forms phenanthridine in excellent yield, and the analogous anils from p-toluidine and a-naphthylamine undergo ring closure under similar conditions. In view of the known trans geometry of the anils and the unlikelihood of trans-cis equilibration under these conditions this reaction deserves further study.187 Potassamide in liquid ammonia also converts 2-bromo-iV-ethyl-3 -hydroxybenzanilide (162) into a mixture of iV-ethyl-3-(164) and N-ethyl-1 -hydroxyphenanthridone (165), probably via the aryne (163).188... [Pg.360]

Reduced phenanthridines have been prepared from anilines and derivatives of cyclohexanone. In the first reported example, Borsche obtained 6,9-dimethyl-7,8,9,I0-tetrahydrophenanthridine (130a) in 15% overall yield by condensing 6-acetyl-3-methylcyclohexanone with aniline and cyclizing the resultant anil (129a) with sulfuric acid. Although the anil (129b) of 2-acetylcyclohexane-l,3-dione cyclizes in... [Pg.353]


See other pages where Anils phenanthridines from is mentioned: [Pg.740]    [Pg.550]    [Pg.740]    [Pg.505]    [Pg.550]    [Pg.740]    [Pg.550]    [Pg.740]    [Pg.740]    [Pg.430]    [Pg.740]    [Pg.353]    [Pg.430]    [Pg.740]    [Pg.740]   
See also in sourсe #XX -- [ Pg.4 , Pg.542 ]

See also in sourсe #XX -- [ Pg.4 , Pg.542 ]




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