合成路线1

Treatment of 1-methoxy-4-nitro-2-(trifluoromethyl)benzene (I) with 4-chlorophenoxyacetonitrile (II) in the presence of potassium tert-butoxide afforded the arylacetonitrile (III). Reductive cyclization of (III) upon treatment with H2 and Pd/C produced indole (IV), which was further reduced to indoline (V) with NaBH3CN and AcOH. Methyl ether cleavage in (V) using ISiMe3 yielded phenol (VI). After protection of the amino group of (VI) as the acetamide (VII), sulfonylation at the phenol group with trifluoromethanesulfonic anhydride and pyridine gave triflate (VIII). The triflate group was then displaced with tetramethyltin in the presence of palladium catalyst to furnish, after hydrolysis of the acetamide, the 5-methyl-6-(trifluoromethyl)indoline (IX).