Phenylhydrazine → 1,2,3,3a,4,5-hexahydro-3a-methyl-6H-pyrido[3,2,1-jk]carbazol-6-one

Beteiligte Stoffe

Reaktionsschritte

A mixture of phenylhydrazine (1.08 g), 1-methyl-2-oxocyclohexanepropionic acid methyl ester (1.98 g), described in Example 6, and ethanol is heated at reflux for 3 hr. The mixture is evaporated to dryness keeping the temperature of the mixture at about 40° C. The residue is heated with 200 ml of 10% aqueous sulfuric acid at reflux temperature for 1 hr. The mixture is cooled and extracted with ether. The extract is washed with 10% sodium hydroxide and brine, and then evaporated. The residue is subjected to chromatography on silica gel. Elution with benzene gives 1,2,3,3a,4,5-hexahydro-3a-methyl-6H-pyrido[3,2,1-jk]carbazol-6-one (6, R1 = CH3, R2 and R3 = H, m = 3 and n = 2) mp 93°-95° C. Further elution with 5% ethyl acetate in hexane as the eluant gives the title compound, nmr (CDCl3) δ 1.27 (s, 3H), 3.6 (s, 3H), 7.0-7.6 (m, 4H), 7.9 (b, 1H).

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