Triphenylphosphine → (S)-4-(1-(2-aminopropyl)-1H-pyrazol-3-yl)-2-chlorobenzonitrile

Participants

Reaction Steps

2-Chloro-4-(1H-pyrazol-3-yl)benzonitrile (4.00 g; 19.64 mmol), (S)-tert-butyl-1-hydroxypropan-2-yl carbamate (3.79 g; 21.61 mmol) and triphenylphosphine were dissolved in dry THF under nitrogen atmosphere and stirred. Diisopropylazodicarboxylate (7.74 ml; 39.3 mmol) was added dropwise and the reaction flask was cooled by ice bath. The reaction was stirred at RT overnight (18 h) and evaporated to dryness. For Boc deprotection 200 ml of 10% HCl/EtOH solution was added to the evaporation residue, stirred for 20 h at RT and evaporated to dryness. 100 ml of water was added to the evaporation residue and washed with 3×120 ml of DCM to remove reactant residues. pH of water phase was adjusted to ˜12 by addition of 2 M NaOH, washed with 3×80 ml of DCM and organic phase dried over Na2SO4. Organic phase was filtered and evaporated to give 2.605 g of the title compound.

Provenance & Evidence