Boron Trichloride → HCID 19594704, compound

Participants

Reaction Steps

Prepare a stirred solution of 5-isopropoxy-2-propoxy-4-methoxy-fluoren-9-one (2.2 g, 6.7 mmole) in 100 mL methylene chloride at 0° under argon. Dropwise add boron trichloride (15.4 mL of 1.0 M in methylene chloride, 15.4 mmole). Monitor the reaction by TLC on aliquots, in 40% ethyl acetate/hexane, quenching with saturated ammonium chloride. After 1 hour, quench the reaction with saturated ammonium chloride. Filter and wash twice with 1.00 mL methylene chloride. Separate the organic layer from the filtrate and wash with brine. Dry with magnesium sulfate, filter and strip the solvent. Chromatograph the crude product dissolving first in methylene chloride, then eluting in 30% ethyl acetate/hexane to give the title compound as a red powder (1.75 g, 6.1 mmole, 92%). Rf =0.54 (EtOAc/hex., 40:60).

Provenance & Evidence