1-Piperidinecarboxaldehyde → 3,5,5,8,8-Pentamethyl-5,6,7,8-tetrahydro-2-naphthalenecarboxaldehyde

Beteiligte Stoffe

Reaktionsschritte

22.2 mL (35.2 mmol) of n-butyl lithium (1.6 M in hexanes) was added. After 1 hours, a solution of 3.95 mL (35.5 mmol) of N-formylpiperidine was added to a solution of 5 g (17.8 mmol) of 2-bromo-3-methyl-5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalene in 50 mL of tetrahydrofuran, cooled in a dry ice/acetone bath. After 30 minutes 30 mL of saturated aqueous ammonium chloride was added to the reaction mixture. The reaction mixture was warmed to room temperature and extracted with ethyl acetate. The organic phase was separated, washed with brine, dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel with gradient elution (hexane-10% ethyl acetate/hexane) to provide 3.5 g (85%) of 2-formyl-3-methyl-5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalene (m.p.: 82.4-84.1° C.).

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