Reaction of 2,7-dialkyl- and 1,2.7-trialkyldecahydro-4-quinolones with triethylaluminum

The reaction of triethylaluminum with stereoisomeric 2,7-dimethyl- and 1,2,7-trimethyldecahydro-4-quinolones and their 7-tert-butyl-substituted analogs was studied. The reaction of triethylaluminum with ketones that have an equatorial 2-CH₃ group proceeds in two directions — reduction of the carbonyl group to an alcohol group and alkylation to give tertiary 4-ethyl-substituted alcohols — in benzene. depending on the reagent ratio. The stereochemistry of the reduction of the carbonyl group depends on the temperature. Only an alkylation product is formed in tetrahydrofuran (THF) and diethyl ether. The reaction of triethylaluminum with ketones that have an axial 2-CH₃ group depends on the nature of the solvent. Epimeric secondary alcohols are formed in toluene at various ratios of the reacting substances, whereas tertiary ethyl-substituted alcohols are formed in THF and diethyl ether.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 946–952, July, 1976.