Methyl iodide → 2-(9H-xanthen-9-yl)propionic acid

Participants

Reaction Conditions

Reaction Steps

To a suspension of 55 mg (1.26 mmol) of sodium hydride previously washed with n-hexane in 5 ml of tetrahydrofuran were added 316 mg (3.13 mmol) of diisopropylamine, and then a solution of 300 mg (1.25 mmol) of 2-(9H-xanthen-9-yl)acetic acid in 4 ml of tetrahydrofuran was dropwise added thereto. After completion of the addition, the resulting mixture was heated under refluxing for 20 minutes and then cooled to -15° C., after which 1.2 ml (1.9 mmol) of a 1.6M n-butyllithium solution were added thereto followed by stirring at the same temperature for 15 minutes. To the mixture was dropwise added a solution of 531 mg of methyl iodide in 2 ml of tetrahydrofuran over a period of 10 minutes, after which stirring was continued at the same temperature for an hour. With ice-cooling the reaction was stopped by addition of a diluted aqueous solution of sodium hydrogencarbonate and the reaction mixture was washed with dichloromethane. The aqueous layer separated was acidified with concentrated hydrochloric acid and extracted twice with ether. The combined ether extracts were subsequently washed with water and a saturated aqueous solution of sodium chloride and the solvent distilled off to give a mixture of the titled Compound A, B and C. The mixture thus obtained was used in the following reaction without purification.

Provenance & Evidence