Uses
(2-Butyl-5-nitrobenzofuran-3-yl)(4-methoxyphenyl)methanone is a reagent in the preparation of heterocyclic benzofuran carboxamides via amidation of heterocyclic acyl chlorides with benzofuranamine. This is also a derivative of Dronedarone (D679445),which is a drug used for the treatment of atrial fibrillation and atrial flutter in patients who have suffered cardiac arrhythmias.
Synthesis
Method-2: A solution of 45 g (0.2 mol) of 2-butyl-5-nitrobenzofuran and 44 g of p-methoxybenzoyl chloride in 300 ml of chlorobenzene was added to a round bottomed flask at 25 °C. To the reaction mixture was slowly added a solution of 40 g of aluminum chloride in 300 ml of chlorobenzene. The reaction system was heated to reflux for 2 hours, subsequently cooled to room temperature and diluted with 40 ml of water. The organic phase was separated and washed sequentially with water and 5% sodium bicarbonate solution. The organic phase was concentrated to dryness under reduced pressure and the resulting product was rapidly crystallized. By recrystallization from 270 ml of isopropanol, 2-butyl-3-(4-methoxybenzoyl)-5-nitrobenzofuran was obtained with a melting point of 94-96°C and HPLC purity >96%.
References
[1] Patent: WO2012/32545, 2012, A1. Location in patent: Page/Page column 32
[2] Journal of the Chinese Chemical Society, 2011, vol. 58, # 7, p. 841 - 845
[3] Patent: US5223510, 1993, A
[4] Journal of Chemical Sciences, 2012, vol. 124, # 5, p. 1077 - 1085
[5] Organic Process Research and Development, 2014, vol. 18, # 1, p. 157 - 162
