Cesium carbonate → HCID 131727416, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 6-(tert-butyl-dimethyl-silanoxy)-1H-indole-2-boronic acid [3.57 g, 9.13 mmol, Intermediate (74), prepared by the application of method described in Example 4-6 of International Patent Application Publication No. WO 02/32861] and 5-(tert-butyl-dimethyl-silanyloxymethyl)-3-iodo-thieno[3,2-c]pyrazole-1-carboxylic acid tert-butyl ester [3.47 g, 7.02 mmol, Intermediate (73)] in solution in 1,4-dioxane (60 mL) was added [1,1′-bis(diphenylphosphino)-ferrocene]dichloropalladium(II) (complex with dichloromethane (1:1)) (385 mg, 0.53 mmol). An aqueous solution (25 mL) of cesium carbonate (9.14 g, 28.08 mmol) was added. The mixture was stirred at 80° C. for 1 hour. It was allowed to cool down to room temperature, and was extracted three times with ethyl acetate. The organic layer was dried over magnesium sulfate and concentrated. The residue was chromatographed through silica gel (n-heptane/ethyl acetate, 95/05 then 90/10) to produce 2-[1-tert-butoxycarbonyl-5-(tert-butyl-dimethyl-silanyloxymethyl)-1H-thieno[3,2-c]pyrazol-3-yl]-6-(tert-butyl-dimethyl-silanyloxy)-indole-1-carboxylic acid tert-butyl ester [3.8 g, 76%, Intermediate (75)]. LC/MS: 714.38 (M+H), RT=3.27 minutes.

Provenance & Evidence