Triphenylphosphine → (6aR,7S,9aS,11S,13aS)-11-azido-5-benzyloxy-2-(t-butoxycarbonyl)-2,3,6,6a,7,8,9,9a,10,11,12,13-dodecahydro-6a,7,10,10-tetramethyl-3-oxo-1H-benzo[8,8a][1]benzopyrano[2,3-e]isoindole

Participants

Reaction Steps

To a solution of Compound (38a) (Step-3 in Example 42) (690 mg, 1.20 mmol) in 35 ml of dry benzene were added dropwise 480 mg (1.83 mmol) of triphenylphosphine and 1.0 ml (1.88 mmol) of 1.9M hydrazoic acid/benzene solution at room temperature with stirring, followed by the addition of 290 μl (1.84 mmol) of diethyl azodicarboxylate and stirring at 80° C. for 20 min. After cooling to room temperature, the solvent was evaporated under reduced pressure. The residue was purified by a column chromatography (Merck, Lobar column, size C; toluene:ethyl acetate=9:1) to give 474 mg (66%) of Compound (44).

Provenance & Evidence