Trimethylsilylacetylene → 1-(Tetrahydro-2H-pyran-2-yl)-5-((trimethylsilyl)ethynyl)-1H-indazole

Participants

Reaction Conditions

Reaction Steps

To a 250-mL pressure tube, 5-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole (11.9 g, 42.3 mmol; Intermediate 1), Pd(Ph3P)2Cl2 (1.48 g, 0.05 mmol), CuI (0.8 g, 4.2 mmol) and THF/triethylamine (5:1, 85 mL) were added. This mixture was degassed with three vacuum/N2 cycles, and then trimethylsilylacetylene (9 mL, 63.5 mmol) was added. The pressure tube was sealed and heated at 80° C. for 2 days. Upon completion by LCMS, the reaction mixture was cooled down to room temperature and filtered through Celite with ethyl acetate (200 mL). The filtrate was concentrated to give the crude product that was used directly in the next step. LCMS: 299 (M+H)+.

Provenance & Evidence