Acetic Acid → 1-Cyclopentyl-4-[2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine

Participants

Reaction Steps

A mixture of 1-[2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine (25 mg, 0.0832 mmol) produced in Example (8b), cyclopentanone (9.1 mg, 0.108 mmol), sodium triacetoxyborohydride (33.5 mg, 0.158 mmol) and acetic acid (0.009 mL, 0.158 mmol) was stirred for 1 hour and 40 minutes 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 organic layer was concentrated to produce a residue, which was purified by NH silica gel column chromatography (ethyl acetate/hexane) to give 1-cyclopentyl-4-[2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine as a colorless oil. δ: 0.92 (s, 6H), 1.13 (s, 6H), 1.16-1.36 (m, 6H), 1.39-1.51 (m, 4H), 1.66-1.76 (m, 2H), 1.86-1.96 (m, 2H), 2.48-2.58 (m, 1H), 2.67 (brs, 4H), 2.89-2.98 (m, 4H), 3.52-3.61 (m, 1H), 7.04-7.14 (m, 3H), 7.21 (d, J=8.8 Hz, 1H).

Provenance & Evidence