Sodium Carbonate → 4'-Methyl-biphenyl-2-carboxylic acid ethyl ester

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4′-Methyl-biphenyl-2-carboxylic acid ethyl ester was prepared in a similar fashion to 4′-methyl-biphenyl-3-carboxylic acid ethyl ester as described. Ethyl 2-bromobenzoate (5.0 g, 21.83 mmol, 1 eq.) and 4-methylbenzeneboronic acid (3.12 g, 22.92 mmol, 1.05 eq.) in THF and aqueous 2M sodium carbonate (24 mL, 2.2 eq.) were treated with palladium(II) acetate (0.49 g, 2.18 mmol, 10 mol %), triphenylphosphine (2.52 g, 9.59 mmol, 4.4×Pd), and copper(I) iodide (0.14 g). When complete, the reaction was worked up as described leaving an orange oil, which was purified, via silica gel flash chromatography using a step gradient of EtOAc in hexane as the mobile phase. Fractions containing the product were pooled leaving 4′-methyl-biphenyl-2-carboxylic acid ethyl ester (5.24 g, 99% yield) as a yellow oil.

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