Hydrochloric Acid → Phenanthren-2-ylboronic acid

Participants

Reaction Conditions

Reaction Steps

Under an argon atmosphere, 98 g of 2-iodophenanthrene and 3 L of dehydrated ether were loaded, and then the reaction solution was cooled to −60° C. After that, 210 mL of a 1.6-M solution of n-butyllithium in hexane were added to the reaction solution. The reaction solution was stirred for 1 hour while its temperature was increased to 0° C. The reaction solution was cooled to −60° C. again, and then a solution of 151 g of triisopropyl borate in 100 mL of dehydrated ether was dropped to the reaction solution. The reaction solution was continuously stirred for 5 hours while its temperature was increased to room temperature. Subsequently, 1 L of a 10% aqueous solution of hydrochloric acid was added to the reaction solution, and then the mixture was stirred for 1 hour. The water layer was removed, and the organic layer was washed with water and a saturated salt solution, and was then dried with magnesium sulfate. After magnesium sulfate had been separated by filtration, the organic layer was concentrated. The resultant solid was washed with hexane and toluene. Thus, 42 g of phenanthrene-2-boronic acid as a target were obtained (in 58% yield).

Provenance & Evidence