Toluene → 2-Butoxycarbonylamino-3-(4'-dibenzofuran-4-yl-biphen-4-ylmethylsulfanyl)-3,3-dimethylpropanoic acid methyl ester

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Reaction Steps

A solution of 2-tert-butoxycarbonylamino-3-(4-bromophenylmethylsulfanyl)-3,3-dimethylpropanoic acid methyl ester (0.432 g, 1 mmol), 4-(4-dibenzofuranyl)benzeneboronic acid (0.305 g, 1.05 mmol) and Pd(PPh3)4 (0.052 g, 5 mol %) in toluene (10 mL) and ethanol (3.0 mL) was treated with 2 M K2CO3 (1.5 mL). The reaction mixture was heated to reflux for 2 h, cooled to room temperature, diluted with ethyl acetate (100 mL). The organic layer was washed successively with 2% aq HCl and sat. aq NaCl, dried over MgSO4 and concentrated. Purification by flash column chromatography (2-10% ethyl acetate in heptane) gave the desired product (430 mg, 72%) as an oil. 1H NMR (CDCl3), δ 8.01 (d, J=8 Hz, 2 H), 7.94 (d, J=8 Hz, 2 H), 7.78 (d, J=8 Hz, 2 H), 7.66 (m, 4 H), 7.42 (m, 5 H), 5.44 (d, J=9 Hz, 1 H), 4.46 (d, J=9 Hz, 1 H), 3.87 (s, 2 H), 3.81 (s, 3 H), 1.44 (s, 9 H). LCMS 618 (M++23).

Provenance & Evidence