Carbon Dioxide → 2,7-dimethyl-9H-fluorene-9-carboxylic acid

Participants

Reaction Steps

A solution of 4,5-dimethylfluorene (5.2 g, 27.0 mmol) in 100 mL of THF at -78° C. was charged with butyl lithium (18.7 mL, 29.0 mmol). The reaction mixture was stirred for 15 min, then CO2 gaseous (5 g, 113.6 mmol) was introduced via cannula over a period of 15 min at -78° C. The reaction mixture was warmed up to room temperature and stirred overnight. Water was added (150 mL) and the layers were separated, the water layer was washed with ethyl acetate (5×20 mL), then acidified with conc. HCl. The precipitate was collected, washed with water and dried to give 2,7-dimethyl-9-fluorenecarboxylic acid (4.24 g, 65.9 %).

Provenance & Evidence