3-Bromobiphenyl → methyl (2RS,4RS)-2-(3-phenylphenyl)-2,4-dimethyl-6-oxocyclohexanecarboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 3-bromobiphenyl (403 μL) in diethyl ether (4 mL) was stirred at −90° C. and treated slowly with n-butyllithium (1.6 M in hexanes, 1.5 mL). The resulting mixture was stirred at −90° C. for 20 min, and then transferred via a cannula to a stirred suspension of copper (I) cyanide (98 mg) in diethyl ether (1 mL) at −78° C. The mixture was stirred for 10 min at −78° C. and then warmed to 0° C. Once at the prescribed temperature, a solution of methyl 2,4-dimethyl-6-oxocyclohex-1-enecarboxylate (100 mg) in diethyl ether (1 mL) was added and the resulting mixture was warmed to rt over 30 min. Once at the prescribed temperature, the mixture was stirred at rt for 3 h. At the conclusion of this period, the mixture was treated with a 9:1 mixture of saturated aqueous ammonium chloride/ammonium hydroxide (10 mL). The resulting mixture was stirred for 10 min and then extracted three times with diethyl ether. The combined organic layers were washed with saturated aqueous ammonium chloride and saturated sodium chloride, dried over sodium sulfate and concentrated under vacuum to yield a residue. The residue was purified by chromatography on silica gel, eluting with 10% ethyl acetate/hexanes, to provide methyl (2RS,4RS)-2-(3-phenylphenyl)-2,4-dimethyl-6-oxocyclohexanecarboxylate (131.5 mg). Mass spectrum m/z 359.34 (M+Na+).

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