Lithium Hexamethyldisilazide → 1-trityl-1H-pyrazolo[4,3-c]pyridin-6-amine

Participants

Reaction Conditions

Reaction Steps

A microwave vial was charged with 6-chloro-1-trityl-1H-pyrazolo[4,3-c]pyridine (1.02 g, 2.58 mmol), Pd2(dba)3 (0.24 g, 0.262 mmol), 2-(dicyclohexylphosphino) biphenyl (0.1 g, 0.285 mmol) and THF (11 mL). The mixture was evacuated and purged with nitrogen 5 times. Lithium bis(trimethylsilyl)amide (4.0 ml, 4.0 mmol, 1M in THF) was added dropwise and the mixture was heated at 70° C. for 2 h. Pd2(dba)3 (0.12 g, 0.131 mmol), 2-(dicyclohexylphosphino) biphenyl (0.05 g, 0.142 mmol) and LiHMDS (2.0 ml, 2.0 mmol, 1M in THF) were added again. After 16 h, the mixture was quenched with saturated NH4Cl and extracted with 2-methyltetrahydrofuran. The organic phase was washed with water, brine, dried (Na2SO4) and concentrated in vacuo to afford a residue, which was purified by chromatography on silica gel (MeOH in DCM, 0-8% 15 CV, 8-10% 10 CV) to afford 1-trityl-1H-pyrazolo[4,3-c]pyridin-6-amine (0.813 g, 2.16 mmol, 84%). MS ESI calc'd. for C25H21N4 [M+H]+ 377, found 377.

Provenance & Evidence