Reaktion #60519

Reaktionsgleichung

4-[2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine-1-carboxylic acid t-butyl ester

sodium acetate

sodium thiosulfate

bromine

→

title compound

Ausbeute 77.1%

4-[4-Bromo-2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine-1-carboxylic acid t-butyl ester

Ausbeute 77.1%

Lösungsmittel

ethyl acetate

methanol

water

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   WaschenThe separated organic layer was washed with brine
2. 2
   Trocknendried over anhydrous sodium sulfate
3. 3
   FiltrationThe desiccant was filtered off
4. 4
   Einengenthe filtrate was concentrated under reduced pressure
5. 5
   SonstigeThe resultant residue was purified by silica gel column chromatography (ethyl acetate/hexane)

Vorschrift

To a mixture of 4-[2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine-1-carboxylic acid t-butyl ester (2.93 g, 7.31 mmol) produced in Example (8a), sodium acetate (6 g, 73.14 mmol) and methanol (50 mL) was added bromine (0.37 mL, 7.22 mmol), followed by stirring for 20 minutes at room temperature under a nitrogen atmosphere. Saturated aqueous solution of sodium thiosulfate, ethyl acetate and water were added to the reaction mixture and extraction was performed with ethyl acetate. The separated organic layer was washed with brine and then dried over anhydrous sodium sulfate. The desiccant was filtered off and the filtrate was concentrated under reduced pressure. The resultant residue was purified by silica gel column chromatography (ethyl acetate/hexane) to give 2.67 g of the title compound as colorless crystals.

Quelle