5-Cyclohexyl-l-indancarboxylic acid

N-chlorosuccinimide (8.2 g.0.0614 mol) was added to a stirred, cooled (ice-water) solution of ( )-5-cyclohexyl-l-indancarboxylic acid (10.0 g, 0.0409 mol) in dimethylformamide (82 ml). The solution was stirred for fifteen minutes at 0°C. thirty minutes at 25°C. nine hours at 50°C, followed by eight hours at 25°C. The solution was diluted with cold water (400 ml) and stirred until the precipitated product turned granular (fifteen minutes). The crude product was collected, washed with cold water, and dried. Crystallization from Skellysolve B with charcoal treatment gave colorless crystals (6.65 g, 58%), MP 149°C to 150°C. The product was recrystallized twice from Skellysolve B to give ( )-6-chloro-5-cyclohexyl-l-indancarboxylic acid as colorless crystals, MP 150.5°C to 152.5°C. 

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