Phenanthridines hydrogenation

Phenanthridine-6-carboxylic acids synthesis, 2, 415 Phenanthridines amination, 2, 236 bromination, 2, 320 hydrogenation, 2, 328 nitration, 2, 319 nomenclature, 2, 5 5-oxides... 

The former passes into the second on further oxidation with hydrogen peroxide, indicating that it is an a-keto-carboxylic acid. Acid (b) loses carbon dioxide on fusion and gives a neutral substance, CjaHj OgN, m.p. 238°, which was shown to be 6 7-methylenedioxy-A-methylphenanthri-done (I), by comparison with a synthetic specimen. The position of the carboxyl group in (b) could not be determined by synthetic methods but is probably at since dihydrolycorineanhydromethine, Cl 7 7 2 ) m.p. 87-5° [picrate, m.p. 174° (dec.) methiodide, m.p. 236° (dec.)] on distillation with zinc dust yields a mixture of phenanthridine, 1-methyl-phenanthridine and 6 7-methylenedioxyphenanthridine, m.p. 142° [picrate, m.p. 257° (dec.)], the identity of the two latter being established by comparison with the synthetic products. These results indicate for lycorineanhydromethine formula (II). 

Moreau, C. Bekakra, L. Olive, J. L., and Geneste, P., Hydrodenitrogenation of Quinoline and Phenanthridine in the Presence of 2, 6-Diethylaniline and Hydrogen-Sulfide Over Molybdenum and Nickel-Molybdenum Sulfides Supported on Zirconia, Titania, Nickel-Aluminates and Magnesium-Aluminates. Bulletin Des Societes Chimiques Beiges, 1991. 100(11-12) pp. 841-847. 

Reaction conditions used for reduction of acridine [430,476, partly hydrogenated phenanthridine [477 and benzo f]quinoline [477 are shown in Schemes 38-40. Hydrogenation over platinum oxide in trifluoroacetic acid at 3.5 atm reduced only the carbocyclic rings in acridine and benzo[h]quinoline, leaving the pyridine rings intact [471]. 

The hydrogenation of phenanthridine at 250 °C under pressure in the presence of a sodium-rubidium catalyst in benzene is reported to give octahydrophenanthridines. Acridine similarly forms a variety of reduction products (71JOC694). 

Upon hydrogenation, from pretazettine (242) the dihydro derivative 260 was obtained which is in equilibrium with the metho salt of dihydrohaemanthidine (261). Furthermore, dihydrohaemanthidine seems to exist in methanol between pH 2 and 12 in the 5,10b-ethano-phenanthridine form. 

Catalytic hydrogenation of the ketoaldoxime (52) gives a hydro-phenanthridine to which structure 53 has been assigned.95... 

Moore and Snyder121 have employed the Schmidt reaction to determine the structure of the hydrocarbon (71), which is one of the products of the self-condensation of acetophenone in polyphosphoric acid. Treatment with hydrogen bromide and dimethyl sulfoxide (DMSO) gives the fluorenol (72), which yields a mixture of 1-methyl-2,4,6-triphenylphenanthridine (73) and 10-methyl-6,7,9-triphenyl-phenanthridine (74) when treated with hydrazoic acid. 

The equilibrium composition was calculated for phenanthridine and a number of other azaaromatics, but no simple relationship existed between these figures and the corresponding pKa values and no quantitative significance could be attached to the presence or absence of peri-hydrogen atoms,235 which have a controlling influence in other reactions of phenanthridine vide infra). (Infrared studies on hydrogen bonding are considered below.)... 

Hydroxy-6-methyl-7,8,9,10-tetrahydrophenanthridine methio-dide is formed directly by the action of methyl iodide on the corresponding base.168 In an interesting reaction with acrylamide in methanolic hydrogen chloride, phenanthridine gives AT-(2-carbamoyl-ethyl)phenanthridinium chloride.288... 

The carbon-nitrogen double bond of phenanthridine can be reduced selectively by hydrogenation over Raney nickel, and attempted reductive dechlorination of 6-chloro derivatives in the presence of this catalyst normally results in the formation of the corresponding 5,6-dihydro compounds.106 Hydrogenations over palladium catalysts are more successful.203 325 Desulfurization of phenanthridinthione... 

The conversion of phenanthridine into an unspecified octahydro-derivative by hydrogenation over a sodium metal-rubidium carbonate catalyst has been reported.334 Hydrogenation of the tetrahydro-phenanthridine (231) over platinum in acetic acid gave, rather surprisingly, the octahydrophenanthridine (232) with loss of meth-oxyl.173... 

Cyanophenanthridine forms the corresponding amide on treatment either with 90% sulfuric acid, or hydrogen peroxide in alkaline solution.296 Complete hydrolysis, followed by decarboxylation to the parent phenanthridine, provides a ready method of structure determination.80... 

Phenanthridine A-oxides are smoothly deoxygenated by phosphorus tribromide in the usual manner.353 Alternatively hydrogenation over Raney nickel can be used to obtain the parent base.353 With ethereal lithium aluminum hydride, dihydrophenanthridine is formed.354... 

The betaine (262) forms phenanthridine almost quantitatively on either heating with concentrated hydrochloric acid at 200° or refluxing with 20% aqueous potassium hydroxide.283 Oxidation of 262 with alkaline hydrogen peroxide gives phenanthridone, whereas with alkaline ferricyanide A7-([Pg.413]

Phenanthridine. Phenanthridine is hydrogenated to the 5,6-dihydro derivative quantitatively over Raney Ni at 20°C and 1 atm H2.105 Phenanthridinium salts were also hydrogenated to the corresponding 5,6-dihydro derivative over platinum oxide or Pd-C in ethanol with addition of a small amount of sodium acetate (eq. 12.53)106 or over platinum oxide in ethanolic hydrogen chloride.107... 

RuHCl(PPh3)3] and [RuH2(PPh3)2(PPh2C6H4)] can reduce polyaromatic compounds under hydrogen. Quinoline (67) and phenanthridine (69) are converted to 1,2,3,4-tetrahydroquinoline (68) and 9,10-dihy-drophenanthridine (70). ... 

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