Cyclopropyl-(2-methyl-4-phenyl-5,6,7,8-tetrahydro-9-thia-1,7-diaza-fluoren-3-yl)-methanone → Cyclopropyl-(2-methyl-4-phenyl-9-thia-1,7-diaza-fluoren-3-yl)-methanone

To a stirred solution of 0.46 g (1.32 mmol) cyclopropyl-(2-methyl-4-phenyl-5,6,7,8-tetrahydro-9-thia-1,7-diaza-fluoren-3-yl)-methanone in 7 ml diphenylethylene was added 230 mg palladium on charcoal 10%. The mixture was stirred over night at 150° C., and then poured onto ethyl acetate (about 150 ml), and extracted three times aqueous HCl (1M). The combined aqueous phases were basified with K2CO3 until ph=8, and then the product was extracted with ethyl acetate. The combined organic phase were dried over sodium sulfate and concentrated in vacuo. Flash chromatography (heptane/ethyl acetate 1:1) afforded 35 mg (8%) cyclopropyl-(2-methyl-4-phenyl-9-thia-1,7-diaza-fluoren-3-yl)-methanone as a light yellow solid. ES-MS m/e (%): 345 (M+H+, 100).