Ytterbium triflate → HCID 66823720, compound

Participants

Reaction Conditions

Reaction Steps

To a mixture of 2-(2′,4′-dichloro-4-cyclopropylbiphenyl-3-yl)-4,4,6,6-tetramethyl-1,5-dioxa-spiro[2.4]heptan-7-one (17.80 g, 0.041 mol) and ytterbium triflate (2.20 g, 4.41 mmol) is added a solution of 5M lithium perchlorate (prepared from 42 ml diethyl ether and 22.30 g lithium perchlorate). The resulting suspension is stirred at room temperature for 17 days, at which stage further diethyl ether (42 ml), lithium perchlorate (22.3 g, 0.21 mol) and ytterbium triflate (19.8 g, 0.035 mol) is added. The reaction mixture is then heated at 27° C. (internal temperature) for 1 day, followed by partitioning between diethyl ether and distilled water. The two phases are separated, the aqueous phase is extracted with diethyl ether (×2), and then all organic fractions are combined, washed with brine then dried over magnesium sulphate. The suspension is filtered and the filtrate is concentrated in vacuo. The crude material is purified by flash column chromatography (ethyl acetate/hexane eluant) to give an oil which is triturated with hexanes to afford 4-(2′,4′-dichloro-4-cyclopropylbiphenyl-3-yl)-2,2,6,6-tetramethylpyran-3,5-dione (2.80 g) as a white solid.

Provenance & Evidence