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

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Reaction Steps

To a solution of 3.0 g (8.15 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 30 ml toluene was added 0.20 g (0.29 mmol) (S)-(−)-2,2′-bis(di-p-tolylphosphino)-1,1′-binaphthyl and 0.12 g (0.12 mmol) di-palladium-tris(dibenzylideneacetone)chloroform complex. After 30 min, 1.0 ml (1.06 g, 9.80 mmol) benzylalcohol and 0.70 g (16.0 mmol) sodium hydride (55–65% dispersion in oil) were added and the reaction mixture was stirred for 3.5 h at 70 deg C. After cooling to room temperature, the reaction mixture was poured onto 10% aqueous sodium carbonate solution and extracted three times with ethyl acetate. The combined organic phases were washed with brine, dried over magnesium sulfate and filtered. After evaporation of the volatile components, the residue was chromatographed on silica gel (0.032–0.063 mm) with ethyl acetate:n-hexane (1:4) as eluant.

Provenance & Evidence