Piperidin-4-ol → 1H-Indolamine

Participants

Reaction Steps

5-(2-Methanesulfonyloxy-ethyl)-2-methyl-1H-indole-3-carboxylic acid benzyl ester (0.300 g, 0.770 mmol, 1 eq, Example 56, Step D) was suspended in Dioxane (20 mL) under Ar. 4-Hydroxypiperidine (0.234 g, 2.320 mmol, 3 eq) was added. The reaction mixture was stirred and heated to reflux for 18 hours. Then the reaction was quenched with saturated sodium bicarbonate and extracted with ethyl acetate (3×). The combined organic phases were washed with brine and dried over Na2SO4. After removing the solvent, the residue was loaded on silica gel and chromatographed, eluting with ethyl acetate/methanol/triethyl amine (100/10/1). 0.200 g (66%) of the indole-amine was obtained as a white solid. This was converted to the .HCl salt. LC/MS (ESI+) 393 (M+1); Anal. Calcd for C24H28N2O3.1HCl.0.4H2O: C, 66.09; H, 6.89; N, 6.42; Found: C, 66.18; H, 6.77; N, 6.30.

Provenance & Evidence