Ammonium fluoride → HCID 68890591, compound

Participants

Reaction Steps

A mixture of 0.75 g (R)-(2-{5-bromo-2-[dimethyl-(1,1,2-trimethyl-propyl)-silanyloxymethyl]-6-methyl-indol-1-yl}-propyl)-carbamic acid tert-butyl ester and 0.52 g ammonium fluoride in 7.5 ml methanol was stirred 18 h at room temperature. The reaction mixture was partitioned between water and ethyl acetate. The phases were separated and the organic phase was washed with 10% citric acid, 10% sodium bicarbonate and brine, dried over magnesium sulfate and evaporated to dryness. The residue was taken up in 6 ml dichloromethane and 0.59 g manganese dioxide was added. The mixture was stirred 2 h at room temperature. The solids were removed by filtration over dicalite and the filtrate was evaporated to dryness. The residue was taken up in 5 ml dichloromethane and 0.072 ml acetic acid and 1.00 g molecular sieve (powder, 4 Å) were added. To the resulting suspension was added 0.536 g triacetoxyborohydride, and the mixture was stirred 1 h at room temperature. Another 0.536 g triacetoxyborohydride was added and the mixture was stirred 1 h. The solids were removed by filtration over dicalite and the filtrate was purified by chromatography on silica gel with hexane:ethyl acetate=2:1 to yield 0.295 g of the title compound as a yellow solid melting at 113–114° C. after crystallisation from hexane.

Provenance & Evidence