PROP-2-YNYL NICOTINATE synthesis

Yield:24641-06-3 72%

Reaction Conditions:

with benzotriazol-1-ol;1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride;N-ethyl-N,N-diisopropylamine in N,N-dimethyl-formamide at 20; for 24 h;Inert atmosphere;

Steps:

Prop-2-yn-1-yl pyrazine-2-carboxylate (2a)

General procedure: Toa suspension of pyrazine-2-carboxylicacid 1a (2 g, 16.11 mmol), HOBt (0.65g, 4.83 mmol) and propargyl alcohol (1.39 mL, 24.17 mmol) in DMF (20 mL) N, N-diisopropylethylamine (4.31 mL, 24.17 mmol) and EDC.HCl (3.39 g, 17.72 mmol)were added consecutively. The reaction mixture was stirred at room temperaturefor 24 hours under nitrogen. Reaction was monitored by TLC. Removal ofsolvent followed by purification using column chromatography eluting withmethanol/dichloromethane (5:95 by volume), to get the title compound as off -white solid, 74.6 % yield, 1.95 g.

References:

Reddyrajula, Rajkumar;Dalimba, Udayakumar [Bioorganic and Medicinal Chemistry Letters,2020,vol. 30,# 2,art. no. 126846] Location in patent:supporting information