Methanol → HCID 19782189, compound

Participants

Reaction Conditions

Reaction Steps

47.4 g (0.22 mol) of the 9-methoxy-phenanthrenone from Example 3 are dissolved in 605 ml of absolute methylene chloride and 440 ml of a 1 molar solution of boron tribromide in methylene chloride are added dropwise at -78° C. The mixture is stirred at -78° C. for 0.5 h, then at +20° C. for 3 h, cooled again to -78° C. and 620 ml of methanol is slowly added. The mixture is allowed to come to 20° C. and is evaporated. The residue is partitioned between 200 ml of CH2Cl2 and 200 ml of 1N NaOH solution, and the NaOH phase is separated and acidified to pH 1 using concentrated HCl solution with ice cooling. The precipitate is filtered off and dried in a high vacuum.

Provenance & Evidence