反应详情

To a solution of the 1-[2-(3,3,4,4-tetramethylcyclopent-1-enyl)phenyl]piperazine (20 mg, 0.0703 mmol) produced in Example (54d) in tetrahydrofuran (1 mL) were added isobutyraldehyde (6.6 mg, 0.0914 mmol), sodium triacetoxyborohydride (19.4 mg, 0.0914 mmol) and acetic acid (0.0076 mL, 0.134 mmol), followed by stirring for 4 hours at room temperature. After further adding isobutyraldehyde (6.6 mg, 0.0914 mmol), sodium triacetoxyborohydride (19.4 mg, 0.0914 mmol) and acetic acid (0.0076 mL, 0.134 mmol) to the mixture, stirring was continued for 3 hours at room temperature. Saturated aqueous solution of sodium hydrogencarbonate was added to the reaction mixture and extraction was performed three times with ethyl acetate. The obtained organic layers were concentrated and the resultant residue was purified by NH silica gel column chromatography (ethyl acetate/heptane) to give 4.3 mg of 1-isobutyl-4-[2-(3,3,4,4-tetramethylcyclopent-1-enyl)phenyl]piperazine as a colorless oil.

1. stirringstirring
2. waitwas continued for 3 hours at room temperature
3. concentrationThe obtained organic layers were concentrated
4. customthe resultant residue was purified by NH silica gel column chromatography (ethyl acetate/heptane)