Potassium Phosphate, Tribasic → (R)-[4'-(1-{4-[3-(t-butyl-dimethyl-silanyloxy)-4,4-dimethyl-pentyl]-3-methyl-phenyl}-1-ethyl-propyl)-2'-methyl-biphenyl-3-yl]-hydroxy-acetic Acid Methyl Ester

Participants

Reaction Steps

Degassed tetrahydrofuran (0.14 mL) was added to t-butyl-(1-{2-[4-(1-ethyl-1-{4-[4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl]-3-methyl-phenyl}-propyl)-2-methyl-phenyl]-ethyl}-2,2-dimethyl-propoxy)dimethylsilane (Example 24-(1); 14.4 mg, 0.0237 mmol), palladium (II) acetate (1.2 mg, 0.0053 mmol), 2-dicyclohexylphosphino-2′,6′-dimethoxy-1,1′-biphenyl (4.5 mg, 0.011 mmol) and potassium phosphate (13.0 mg, 0.0612 mmol). The mixture was stirred in a nitrogen atmosphere for three minutes, followed by addition of (R)-(3-chloro-phenyl)-hydroxy-acetic acid methyl ester (Example 156-(1); 0.006 mL, 6.5 mg, 0.032 mmol). After replacement with nitrogen, the mixture was heated while stirring at an external temperature of 60 to 70° C. for four hours. The reaction mixture was diluted with diethyl ether and filtered through cotton plug, and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel chromatography (hexane/ethyl acetate=7/1) to give the title compound (3.6 mg, 24%).

Provenance & Evidence