Lithium Hydroxide → HCID 86663670, compound

Participants

Reaction Steps

To a solution of 4-[1-(4′-chloro-4-cyclopropyl-2′-fluorobiphenyl-3-yl)methylidene]-2,2,5,5-tetramethyldihydrofuran-3-one (19.80 g, 0.050 mol) in methanol (830 ml) at 35° C. is added 50% aqueous hydrogen peroxide (5.00 ml, 0.075 mmol), followed immediately by 2M lithium hydroxide (5.00 ml, 0.01 mol) solution. The mixture is stirred at this temperature for a further 2 hours, then allowed to cool to room temperature. Then reaction mixture is quenched with 10% sodium metabisulfite (negative KI-starch indicator test) then diluted with diethyl ether. Most of the methanol is removed under vacuum, and the crude mixture is partitioned between distilled water and diethyl ether. The aqueous phase is further extracted with diethyl ether (×2), then all organics are combined and washed with saturated sodium bicarbonate (×2) then brine. After anhydrousing over magnesium sulfate the suspension is filtered and the filtrate concentrated in vacuo to afford 2-(4′-chloro-4-cyclopropyl-2′-fluorobiphenyl-3-yl)-4,4,6,6-tetramethyl-1,5-dioxa-spiro[2.4]heptan-7-one (18.2 g) as an orange foam. This material is of sufficient purity to use directly in the next step without further purification.

Provenance & Evidence