I[C:2]1[CH:7]=[CH:6][C:5]([O:8][CH3:9])=[CH:4][CH:3]=1.[CH3:10][O:11][C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][C:13]=1B(O)O.C(=O)([O-])[O-].[K+].[K+]>[Br-].C([N+](CCCC)(CCCC)CCCC)CCC>[CH3:9][O:8][C:5]1[CH:6]=[CH:7][CH:2]=[CH:3][C:4]=1[C:15]1[CH:16]=[CH:17][C:12]([O:11][CH3:10])=[CH:13][CH:14]=1At 120° C., p-iodoanisole is reacted with 2-methoxyphenylboronic acid in the presence of palladium tetraphenyl phosphate, potassium carbonate and the phase transfer catalyst, tetrabutyl ammonium bromide to yield 2,4′-dimethoxybiphenyl (66%), which is then brominated at 0° C. in ethylene dichloride to produce 5,5′-dibromo-2,4′-dimethoxybiphenyl in 80% yield. n-butyl bromide is reacted with the dibromo intermediate in the presence of magnesium and cuprous iodide at −10° C. to produce in 50% yield 3′,5-dibutyl-2,4′-dimethoxy-1,1′-biphenyl. Demethylation with boron tribromide gives 3′,5-dibutyl-2,4′-dihydroxy-1,1′-biphenyl (17% yield).
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