Synthesis
GENERAL METHODS: A mixture of compounds 1b, 2b or 3b (1.8 g, 5.1 mmol) with 10% Pd/C (0.2 g) in methanol (70 mL) was stirred overnight at room temperature in a hydrogen atmosphere. Upon completion of the reaction, the reaction mixture was treated by diafiltration, followed by addition of water (50 mL) to the filtrate and extraction with dichloromethane three times (50 mL each). The organic layers were combined, washed with brine, dried over anhydrous sodium sulfate and subsequently concentrated under vacuum. The crude product was purified by column chromatography to afford the target products 1c-3c as brown solids in 56.0%, 55.0% and 69.0% yields, respectively.
References
[1] RSC Advances, 2016, vol. 6, # 87, p. 84284 - 84293
[2] RSC Advances, 2014, vol. 4, # 16, p. 7959 - 7966
[3] Dyes and Pigments, 2015, vol. 121, p. 170 - 177
[4] Annali di Chimica (Rome, Italy), 1959, vol. 49, p. 985,992,994
[5] Arzneimittel-Forschung, 1965, vol. 15, # 6, p. 604 - 608
