Pyridine → 2-[N-(5-bromo-2-hydroxybenzyl)-N-ethylamino]-5-cyanopyridine

Participants

Reaction Steps

2-[N-(5-Bromo-2-hydroxybenzyl)-N-ethylamino]pyridine-5-carboxamide (example 4) (1.93 g, 5.5 mmol) was suspended in THF (30 ml) and treated with pyridine (1.15 g, 14.25 mmol, 1.15 ml) followed by trifluoroacetic anhydride (3.4 g, 16 mmol) whilst stirring at ambient temperature. The white solid dissolved and there was a slight exotherm. The resultant solution was left overnight at ambient temperature. The mixture was then evaporated to low volume, a saturated aqueous solution of sodium bicarbonate was added and the mixture stirred at ambient temperature for 30 minutes. The mixture was again evaporated to low volume and the white solid that precipitated was filtered, washed with water and sucked dry (1.68 g). The solid was purified by MPLC on silica to give 2-[N-(5-bromo-2-hydroxybenzyl)-N-ethylamino]-5-cyanopyridine as a white solid (1.15 g, 63%).

Provenance & Evidence