Zkusil bych ochranit isatin NH pomoci PMB nebo SEM/ Tady je procedura od Dylana Stiles (aka Tenderbutton):
Isatin (18.87 g, 0.128 mol) was dissolved in 250 mL of DMF. After cooling to 0 ºC, NaH (3.232 g, 0.135 mol) was added, resulting in the evolution of a considerable amount of gas. The slurry was stirred for 20 min, allowing to warm to room temperature. PMB-Cl (20 mL, 23.1 g, 0.148 mol) was added via syringe, and the reaction was stirred overnight. The slurry was poured into 1 L of ice water and stirred until all the ice melted. The precipitate was collected by filtration, then recrystallized from 2 L of boiling ethanol. Yield: 30.72 g (90%). Bright orange shiny flakes. 1H NMR (200 MHz)
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