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

Participants

Reaction Steps

To a solution of 2.00 g (4R,9aR)-6-Hydroxymethyl-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester in 20 ml dichloromethane was added 6.00 g manganese dioxide in 3 portions of 2.00 g in intervals of 1 h at room temperature while stirring. The reaction mixture was stirred for 2 more hours at room temperature. The solids were removed by filtration over dicalite and the mother liquor was evaporated and the residue was purified by chromatography on silica gel with heptane:ethyl acetate=1:1 to yield 1.600 g of the title compound as slightly yellow crystals (MS: 316.0 (M+H+))

Provenance & Evidence