Sodium metaborate → HCID 57552324, compound

Participants

Reaction Steps

18.2 g (56.6 mmol) of methyl 5-propyl-2-trifluoromethanesulfonyloxycyclohex-1-enecarboxylate, 21.5 g (74.6 mmol) of 4-ethoxy-3-fluoro-2-(2-methoxyethoxymethoxy)benzeneboronic acid, 1.5 ml of water, 33 g (120 mmol) of sodium metaborate, 1.12 g (1.6 mmol) of bis(triphenylphosphine)palladium(II) chloride and 0.1 ml (1.6 mmol) of hydrazinium hydroxide are heated under reflux overnight in 300 ml of tetrahydrofuran. After addition of water, the aqueous phase is separated off and extracted twice with MTB ether. The combined organic phases are washed with saturated sodium chloride soln. and dried over sodium sulfate. The solvent is removed under reduced pressure, and the residue is filtered through silica gel with n-heptane/MTB ether (6:4), giving 3-ethoxy-4-fluoro-8-propyl-7,8,9,10-tetrahydrobenzo[c]chromen-6-one as colourless crystals.

Provenance & Evidence