Trifluoroacetic acid → 8-(6-hydroxy-2,3-dihydrobenzofuran-5-yl)-6-((5-(trifluoromethyl)furan-2-yl)methyl)-6,8-dihydro-2H-[1,4]dioxino[2,3-f]indol-7(3H)-one

Participants

Reaction Steps

To a solution of 8-hydroxy-8-(6-hydroxy-2,3-dihydrobenzofuran-5-yl)-6-((5-(trifluoromethyl)furan-2-yl)methyl)-6,8-dihydro-2H-[1,4]dioxino[2,3-f]indol-7(3H)-one (1.81 g, 3.70 mmol) in dichloromethane (50 mL) were added triethylsilane (6.0 mL) and trifluoroacetic acid (10 mL) at 0° C. The resultant mixture was stirred at 0° C. for 2 h and concentrated in vacuo to dryness to afford 8-(6-hydroxy-2,3-dihydro-1-benzofuran-5-yl)-6-{[5-(trifluoromethyl)furan-2-yl]methyl}-2,3,6,8-tetrahydro-7H-[1,4]dioxino[2,3-f]indol-7-one (1.70 g, 97%): MS (ES+) m/z 473.9 (M+1).

Provenance & Evidence