Synthesis
General procedure for the synthesis of 4-aminoisobenzofuran-1(3H)-one from 4-nitroisobenzofuran-1(3H)-one: 4-nitroisobenzofuran-1(3H)-one (1.0 g, 5.58 mmol) and 10% Pd/C (0.1 g) were suspended in ethyl acetate (30 mL). The reaction system was purged with hydrogen (1 atm) and stirred for 3 hours at 25°C. After completion of the reaction, the mixture was filtered to remove the catalyst and the filtrate was concentrated to afford 4-aminoisobenzofuran-1(3H)-one (0.8 g, 96% yield) as an off-white solid. Mass spectrum (ESI) m/z: 150 (M + 1)+. 1H-NMR (400 MHz, CDCl3) δ 3.82 (s, broad peak, 1H), 5.19 (s, 3H), 6.91-6.95 (m, 1H), 7.32-7.36 (m, 2H).
References
[1] Patent: US2010/35883, 2010, A1. Location in patent: Page/Page column 48
[2] Patent: WO2011/130661, 2011, A1. Location in patent: Page/Page column 84-85
[3] Journal fuer Praktische Chemie/Chemiker-Zeitung, 1993, vol. 335, # 1, p. 17 - 22
[4] Advanced Synthesis and Catalysis, 2010, vol. 352, # 11-12, p. 1834 - 1840
[5] Chemistry - A European Journal, 2011, vol. 17, # 21, p. 5903 - 5907
