Hydrochloric Acid → Benzo[c]phenanthren-5-ylboronic acid

Participants

Reaction Conditions

Reaction Steps

A flask was charged with 10.1 g of 5-bromobenzo[c]phenanthrene in an argon atmosphere. 400 mL of dehydrated diethyl ether was then added to the flask. After cooling the reaction solution to −40° C., 22 mL of a 1.6 M hexane solution of n-butyllithium was added to the reaction solution. The mixture was heated to 0° C., and stirred for 1 hour. After cooling the reaction solution to −60° C., a dehydrated diethyl ether (10 mL) solution of 14.4 g of triisopropyl borate was added dropwise to the reaction solution. The reaction solution was stirred for 5 hours while warming the reaction solution up to room temperature. After the addition of 100 mL of a 10% hydrochloric acid aqueous solution, the mixture was stirred for 1 hour. After removing the aqueous phase, the organic phase was washed with water and a saturated sodium chloride solution, and dried over magnesium sulfate. After removing magnesium sulfate by filtration, the organic phase was concentrated. The resulting solid was washed with hexane to obtain 5.37 g of the target benzo[c]phenanthrene-5-boronic acid (yield: 60%).

Provenance & Evidence