1-{[5-(1-methyl-1H-indol-2-yl)-pyridin-3-ylamino]-methyl}-cyclobutanecarboxylic acid ethyl ester → 2-methyl-1-(1-{[5-(1-methyl-1H-indol-2-yl)-pyridin-3-ylamino]-methyl}-cyclobutyl)-propan-1-one

Participants

Reaction Steps

To a solution of 1-{[5-(1-methyl-1H-indol-2-yl)-pyridin-3-ylamino]-methyl}-cyclobutanecarboxylic acid ethyl ester (Example 213b, 0.45 g, 1.21 mmol) in THF (150 mL) cooled with an ice-water bath is added iPrMgCl (2.0M in THF, 2.43 mL, 4.85 mmol) dropwise. After 45 min, the mixture is quenched with 1M aqueous NaHSO4 (5 mL), washed with saturated aqueous sodium bicarbonate and brine, dried over MgSO4, filtered and concentrated in vacuo. The residue is purified by silica gel flash chromatography (heptane-ethyl acetate, 3:2 to 1:1), followed by purification by RP HPLC on an Xbridge RP18 eluting with a gradient of acetonitrile in 0.1% aqueous NH4OH to give 2-methyl-1-(1-{[5-(1-methyl-1H-indol-2-yl)-pyridin-3-ylamino]-methyl}-cyclobutyl)-propan-1-one.

Provenance & Evidence