Tributylphosphine → (diphenylmethyl)-5'-methylspiro[furo[2,3-f][1,3]benzodioxole-7,3'-indol]-2'(1'H)-one

Participants

Reaction Steps

To a solution of 1-(diphenylmethyl)-3-(6-hydroxy-1,3-benzodioxol-5-yl)-3-(hydroxymethyl)-5-methyl-1,3-dihydro-2H-indol-2-one (1.31 g, 2.72 mmol) in ethyl acetate (50.0 mL) was added tributylphosphine (0.82 g, 4.07 mmol). A solution of di-tert-butyl azodicarboxylate (0.94 g, 4.07 mmol) in ethyl acetate (45.0 mL) was added to the above reaction mixture over a period of 5 minutes. After stirring for 10 minutes under N2, the reaction was quenched with saturated aqueous ammonium chloride (60.0 mL). The organic layer was separated and washed with 1.0 N hydrochloric acid solution (3×100 mL), dried over sodium sulfate and filtered. The filtrate was concentrated in vacuo to dryness. The residue was subjected to column chromatography eluting with ethyl acetate/hexane (10-50%) to afford the title compound (0.98 g, 78% yield): 1H NMR (300 MHz, CDCl3) δ 7.40-7.25 (m, 10H), 7.02, (s, 1H), 6.96 (s, 1H), 6.79 (d, 1H), 6.50 (s, 1H), 6.36 (d, 1H), 6.08 (s, 1H), 5.86 (d,2H), (4.82 (ABq, 2H), 2.20 (s, 3H).

Provenance & Evidence