Imidazole → HCID 86757593, compound

Participants

Reaction Conditions

Reaction Steps

(S, R)-1-benzyloxycarbonyl-2-(1-hydroxyethyl)-4-tert-butyloxycarbonyl-piperazine (7.6 g) was dissolved in 208 mL of toluene. While stirring, imidazole (3,5 g), triphenylphospine (15.31 g), and Zn(N3)2.pyr2 (14.11 g) were added in that order. The mixture was cooled to 0° C. and diethylazodicarboxylate (10.2 g) was added dropwise. The mixture was warmed to room temperature and stirred for 1 hour, then decanted into a separatory funnel and extracted with 2×360 mL of ethyl acetate. Any solids in the reaction flask were dissolved with 1N HCl, poured into the separatory funnel, and extracted with 2×760 mL of ethyl acetate. The combined organics were washed with 760 mL each of saturated NaHCO3 and brine, dried with Na2SO4, and concentrated. The residue was purified by flash chromatography, eluting with 4:1 hexanes-ethyl acetate to provide 4.19 g of the title compound. Mass spectrum (ESI) 334.1 (M−55).

Provenance & Evidence