Cesium carbonate → 1-(1,4-Dioxaspiro[4.5]dec-8-yl)-4-iodo-1H-pyrazole

Beteiligte Stoffe

Reaktionsschritte

A mixture of Toluene-4-sulfonic acid 1,4-dioxa-spiro[4.5]dec-8-yl ester (4.47 g; 13.9 mmol; 1.0 eq.), 4-Iodo-1H-pyrazole (2.69 g; 13.9 mmol; 1.0 eq.) and cesium carbonate (6.78 g; 20.8 mmol; 1.5 eq.) was heated in DMA (50.0 mL) at 100° C. for 3 h. It was then allowed to cool to RT, diluted with EtOAc and washed with water and brine. Aqueous phases were back-extracted with EtOAc. Combined organic phases were finally dried over sodium sulfate, filtered and concentrated to give 6.32 g of a yellow oil. Recrystallisation in iPrOH afforded the title compound as a white powder (2.81 g, 61%). HPLC (Condition A): Rt 3.46 min (purity 100%). MS (ESI+): 335.1.

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