(4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester → (4R,9aR)-6-Cyano-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of 0.20 g (0.54 mmol) (4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester (Example 5, intermediate b) in 5 ml dioxane were added 195.0 mg (2.17 mmol) copper(I)cyanide, 22.5 mg (22 μmol) tris(dibenzylideneacetone)dipalladium(0), 48.2 mg (87 μmol) 1,1′-bis(diphenylphosphino)ferrocene and 0.13 g (0.81 mmol) tetraethylammonium cyanide and the suspension was heated to reflux and stirred for 1.5 h. The mixture was cooled to room temperature, filtered and the filtrate was washed successively with aqueous saturated sodium bicarbonate solution, aqueous 10% citric acid solution, brine, dried over magnesium sulfate, filtered and evaporated. The residue was immediately purified by flash column chromatography on silica gel (0.032–0.063 mm) to afford the desired compound as a colorless foam (98.4%).

Provenance & Evidence