Synthesis
Hydrochloride (0.32 ml) was added in a solution of 5-Triphenyl methyl-tetrahydro-5, 6, 7,7a 4H- theino-[3,2-c]- pyridone-2 (100 g, 0.25 moles) in acetone (500 ml) at 25 °C. Stir the reaction mass for 1 hr at 50 °C, then cool the reaction mass to 25 °C and stir for 8 to 10 hrs at 25 °C. Filter the product and wash it with acetone. Dry the material under vacuum at 60 °C to obtain 5, 6, 7,7a -Tetrahydro-4H- theino-[3,2-c]- pyridone-2 hydrochloride (42 g, 99percent).
References
[1] Patent: WO2012/1486, 2012, A1. Location in patent: Page/Page column 20
[2] Journal of Organic Chemistry, 2015, vol. 80, # 14, p. 7019 - 7032
[3] Patent: WO2009/62044, 2009, A2. Location in patent: Page/Page column 40
[4] Patent: WO2011/42918, 2011, A2. Location in patent: Page/Page column 43-44
[5] Patent: WO2011/92720, 2011, A2. Location in patent: Scheme 1