Reaction #60466

Reaction equation

sodium hydrogencarbonate

1-[4-methyl-2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine

propionaldehyde

sodium triacetoxyborohydride

→

1-[4-methyl-2-(3,3,5,5-tetramethylcyclohexyl)phenyl]-4-propylpiperazine

Yield 89.7%

Solvents

tetrahydrofuran

ethyl acetate

Conditions

Workup

1. 1
   DryingThe separated organic layer was dried over anhydrous sodium sulfate
2. 2
   FiltrationThe desiccant was filtered off
3. 3
   Concentrationthe filtrate was concentrated under reduced pressure
4. 4
   OtherThe resultant residue was purified by NH silica gel column chromatography (ethyl acetate/heptane)

Procedure

To a mixture of 1-[4-methyl-2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine (55 mg, 0.175 mmol) produced in Example (70b), propionaldehyde (20 mg, 0.350 mmol) and tetrahydrofuran (2 mL) was added sodium triacetoxyborohydride (75 mg, 0.350 mmol), followed by stirring for 1 hour and 15 minutes at room temperature. Saturated aqueous solution of sodium hydrogencarbonate was added to the reaction mixture and extraction was performed with ethyl acetate. The separated organic layer was dried over anhydrous sodium sulfate. The desiccant was filtered off and the filtrate was concentrated under reduced pressure. The resultant residue was purified by NH silica gel column chromatography (ethyl acetate/heptane) to give 56 mg of 1-[4-methyl-2-(3,3,5,5-tetramethylcyclohexyl)phenyl]-4-propylpiperazine as a colorless solid.

Source