Dichloromethane → HCID 53887193, compound

Participants

Reaction Steps

The compound (5.16 g) obtained in Example 63 was dissolved in tetrahydrofuran (100 ml) under a nitrogen atmosphere and then a methylene chloride solution (40 ml) of boron tribromide (1.6 ml) was added at -78° C., after which the temperature was elevated to room temperature over one hour and the stirring was further conducted at room temperature for 3 hours. The reaction mixture was neutralized with a 15% aqueous sodium hydroxide solution and then subjected to extraction with ethyl acetate and methanol. The organic layer was dried over sodium sulfate and then concentrated under reduced pressure. The residue was purified by a silica gel column chromatography (chloroform alone→chloroform/methanol=50/1→33/1) to obtain the desired compound (2.67 g).

Provenance & Evidence