29709-35-1

2-(1H-Pyrrol-1-yl)ethanamine may be used in the preparation of dihydropyrrolo[2′,1′:3,4]pyrazino[2,1-a]isoindolones by reacting with 2-formylbenzoic acids or 2-acetylbenzoic acid via N-acyliminium cation aromatic cyclizations. This product was previously listed as CBR00085.

Step I: Synthesis of 2-(1H-pyrrol-1-yl)ethylamine Anhydrous sodium hydroxide (71.6 g, 1.79 mol, 4.0 eq.) was added to an acetonitrile solution (500 mL) of 1H-pyrrole (30.0 g, 0.447 mol, 1.0 eq.) at 0 °C and the mixture was stirred for 1 hour at room temperature. Subsequently, 2-chloroethylamine hydrochloride (59.72 g, 0.514 mol, 1.15 eq.) was added and the reaction mixture was heated to reflux for 12 hours. After completion of the reaction, the mixture was cooled to room temperature, filtered through diatomaceous earth and the filter cake was washed with dichloromethane (200 mL). The filtrate was concentrated under reduced pressure to give the crude product. The crude product was purified by vacuum distillation to afford the target compound 2-(1H-pyrrol-1-yl)ethylamine as a colorless oil. Yield: 50% (25.0 g, 0.227 mol).

[1] Organic Letters, 2011, vol. 13, # 17, p. 4490 - 4493
[2] Patent: CN108250128, 2018, A. Location in patent: Paragraph 0787; 0789; 0790; 0791
[3] Advanced Synthesis and Catalysis, 2014, vol. 356, # 4, p. 851 - 856
[4] Chemistry - A European Journal, 2017, vol. 23, # 68, p. 17279 - 17289
[5] Patent: US2012/58999, 2012, A1. Location in patent: Page/Page column 20-21