Methanesulfonic Acid → HCID 18955530, compound

Participants

Reaction Conditions

Reaction Steps

2.41 g (20.0 mmol) of pivaloyl chloride are added dropwise over a period of 10 minutes to a suspension of 2.70 g (10.0 mmol) of 3-(4-ethoxyphenyl)-5-hydroxybenzofuran-2-one (compound (136), Table 1, Example 1) in 10 ml of xylene and 0.1 ml of methanesulfonic acid which is stirred at 95° C. under a nitrogen atmosphere. The clear, homogeneous reaction mixture is then refluxed for 2.5 hours and then concentrated under a slight vacuum. The residue is taken up in dichloromethane and washed with saturated sodium bicarbonate solution and water. The organic phases are combined, dried over sodium sulfate and concentrated on a vacuum rotary evaporator. The residue gives 1.95 g (55%) of 3-(4-ethoxyphenyl)-5-pivaloyloxybenzofuran-2-one, oil (compound (135), Table 1).

Provenance & Evidence