2-Tert-butoxycarbonyloxy-5-fluoro-4-iodo-indole-1-carboxylic acid tert-butyl ester → 2-tert-butoxycarbonyloxy-4-[3-(1-tert-butoxycarbonyl-3,4-dimethyl-1H-pyrrol-2-yl)-3-hydroxy-prop-1-ynyl]-5-fluoro-indole-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

A solution of 2-tert-butoxycarbonyloxy-5-fluoro-4-iodo-indole-1-carboxylic acid tert-butyl ester (from Example 2 above) (1 g, 2.22 mmol), and 3,4-dimethyl-2-(1-hydroxy-prop-2-ynyl)-pyrrole-1-carboxylic acid tert-butyl ester (from Example 45 above) (1.38 g, 5.54 mmol) in dry THF(12 mL) and triethylamine(Aldrich, 12 mL) was degassed by bubbling argon through the solution for 10 minutes. At this time copper(I) iodide (Aldrich, 84.4 mg, 0.44 mmol) and (Ph3P)4Pd (0.25 g, 0.22 mmol) were added, and the reaction mixture was stirred at room temperature overnight. The reaction mixture was filtered and concentrated in vacuo. Flash chromatography (silica gel, 85:15 hexanes/ethyl acetate) afforded 2-tert-butoxycarbonyloxy-4-[3-(1-tert-butoxycarbonyl-3,4-dimethyl-1H-pyrrol-2-yl)-3-hydroxy-prop-1-ynyl]-5-fluoro-indole-1-carboxylic acid tert-butyl ester as an orange oil. (Yield 0.76 g, 57%).

Provenance & Evidence