1,2-Dimethoxyethane → 2-{5-[4-(5-Bromo-thiophen-2-yl)-phenyl]-1H-imidazol-2-yl}-pyrrolidine-1-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 2,5-Dibromo-thiophene (4.93 g), 2-{5-[4-(4,4,5,5-Tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-1H-imidazol-2-yl}-pyrrolidine-1-carboxylic acid tert-butyl ester (0.896 g, prepared according to WO2008021927 A2), and Pd(PPh3)4 (0.118 g) in 2M K2CO3 (3.06 mL)/dimethoxyethane (6.12 mL) was heated at 90° C. for 8 hours. Reaction mixture was cooled, diluted with ethyl acetate and washed with brine, dried (MgSO4), concentrated and purified by flash column chromatography (silica gel, 0 to 100% ethyl acetate/hexanes) to give 2-{5-[4-(5-Bromo-thiophen-2-yl)-phenyl]-1H-imidazol-2-yl}-pyrrolidine-1-carboxylic acid tert-butyl ester (0.955 g): LCMS-ESI+: calc'd for C22H25BrN3O2S: 475.42 (M+H+). Found: 473.8, 475.9 (M+H+).

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