Trifluoroacetic acid → HCID 68700636, compound

Participants

Reaction Conditions

Reaction Steps

A 2 L, 3-necked round bottomed flask equipped with a condenser, heating mantle, overhead stirrer and a thermocouple was charged with 6-(3-Amino-benzoyl)-1,3-dihydro-indol-2-one (47 g, 0.19 mol) then trifluouroacetic acid (TFA, 294 mL). The initial reaction was exothermic raising the reaction temperature from 20° C. to 32° C. Triethylsilane (148 mL) was added and the reaction mixture was heated at 55° C. for 3 d. During this period, additional triethylsilane (518 mL total, by 2.5 equivalents at a time) was added until the reaction was complete by thin layer chromatographic analysis (ethylacetate/Hexanes 8:2). The thin layer chromatography plate was viewed with short wavelength UV and 12 stain. The reaction mixture was concentrated to remove the TFA and the remaining solids were washed with methyl t-butyl ether (500 mL) and THF (1 L). The solids were then suspended in water (500 mL) and saturated sodium bicarbonate (500 mL) and allowed to stir overnight. The suspension was then filtered and the solids collected were washed with water (300 mL). Subsequently the solids were dried in the vacuum oven at 40° C. to afford pure 6-(3-Amino-benzyl)-1,3-dihydro-indol-2-one in 75% yield (33.4 g, 0.14 mol).

Provenance & Evidence