HCID 117689908, compound → HCID 90384192, compound

Participants

Reaction Conditions

Reaction Steps

A polyphosphoric acid (1.86 g) was suspended in chlorobenzene (8 mL), and a solution (8 mL) of the compound (730 mg, 2.60 mmol) of Step 1 of Example 51 in chlorobenzene was added thereto at 120° C., and stirred at 140° C. overnight. After further stirred at 155° C. two nights, the resultant was returned to room temperature, and the reaction solution was concentrated under reduced pressure, and diluted with ethyl acetate. To the mixture liquid, a 1 N sodium hydroxide aqueous solution was added under ice-cooling for the neutralization, and the insoluble material was filtered off. The filtrate was extracted with ethyl acetate, washed with saturated brine, and then dried over anhydrous magnesium sulfate. The resultant was concentrated under reduced pressure. The resulting residue was purified by silica gel chromatography (hexane) to thus obtain the title compound.

Provenance & Evidence