Acetic Acid → 5-(tetrahydro-2H-thiopyran-4-yl)-N,N-bis((2-(trimethylsilyl)ethoxy)methyl)pyrazolo[1,5-a]pyrimidin-7-amine

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-aminopyrazole (19.3 mmol, 1.61 g) and compound 3-oxo-3-(tetrahydro-2H-thiopyran-4-yl)propanenitrile (21.3 mmol, 3.60 g) in acetic acid (40 mL) was heated at 100° C. in a sealed tube overnight. After cooling to rt, all the volatiles were removed under reduced pressure to afford a light brownish oil. This brownish oil was dissolve in DCM (60 mL), and then SEMCl (67.6 mmol, 11.9 mL) and DIPEA (135 mmol, 23.5 mL) were added. The resulting reaction mixture was stirred at 45° C. for 1 h. After cooling to rt, all the volatiles were removed under reduced pressure. The residue was diluted with EtOAc (300 mL), filtered and washed with EtOAc. The filtrate was concentrated and the crude product was purified by a SiO2 column (0-30%) to afford compound, 5-(tetrahydro-2H-thiopyran-4-yl)-N,N-bis((2-(trimethylsilyl)ethoxy)methyl)pyrazolo[1,5-a]pyrimidin-7-amine as a light brownish oil (9.23 g, 97%). HPLC-MS TR=3.09 min (UV 254 nm, 5 min method); mass calculated for formula C23H42N4O2SSi2 494.3, observed LCMS m/z 495.1 (M+H).

Provenance & Evidence