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

Participants

Reaction Conditions

Reaction Steps

Under an argon atmosphere, 10.1 g of 5-bromobenzo[c]phenanthrene which had been prepared in Synthesis Example 1 was placed in a flask. 400 mL of dehydrated ether was added to this flask. The reaction solution was cooled to −40° C., and 22 ml of 1.6M hexane solution of n-butyllithium was added. The resultant was heated to 0° C., and stirred for an hour. The reaction solution was cooled to −60° C., and 10 mL of a dehydrated ether solution of 14.4 g of triisopropyl borate was dripped. The reaction solution was stirred for 5 hours while heating to room temperature. 100 mL of a 10% hydrochloric acid solution was added and the mixture was stirred for an hour. An aqueous phase was removed, and an organic phase which had been separated was washed with water and saturated brine, and then dried with magnesium sulfate. After the magnesium sulfate was filtered out, the organic phase was concentrated. The solids obtained were washed with hexane, whereby 5.37 g (yield: 60%) of benzo[c]phenanthrene-5-boronic acid was obtained.

Provenance & Evidence