Abstract
Application of dichlorocarbene to 1-alkylquinolinium halide (1), obtained easily from commercial quinoline derivatives and alkyl halide, in chloroform afforded 1, 1-dichloro-3-methyl (or ethyl)-1a, 2, 3, 7b-tetrahydro-2-(trichloromethyl)-1H-cyclopropa [c] quinoline derivatives (6) in a high yield, by the introduction of carbon chains into 2, 3, and 4 positions adjoining the ring nitrogen atom. Synthesis of 6 had hitherto been difficult, and the present method offers a novel two-step synthesis of 6 from commercial quinoline derivatives. Treatment of 6 with lithium aluminum hydride in tetrahydrofuran produced 1, 1-dichloro-2-(dichloromethyl)-3-methyl (or ethyl)-1a, 2, 3, 7b-tetrahydro-1H-cyclopropa [c]-quinoline and its treatment with conc. hydrochloric acid in methanol gave 1, 1-dichloro-2-(methoxycarbonyl)-3-methyl (or ethyl)-1a, 2, 3, 7b-tetrahydro-1H-cyclopropa [c] quinoline. However, the compound (1c) having a benzyl group in 1-position failed to give a dichlorocarbene adduct, and the compounds (1k, m) having a nitro group in 5- or 6-position did form dichlorocarbene adducts.
