3-Bromo-1,1-diethoxypropan-2-one → 2-Amino-4-diethoxymethyl-imidazole-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-bromo-1,1-diethoxy-propan-2-one (21.3 g, 95 mmol) (Step 179.9) and N-tert-butoxycarbonylguanidine (45.3 g, 284 mmol, 3 equiv) (Step 179.10) was stirred at 50° C. for 8 h. The reaction mixture was concentrated, diluted in EtOAc/H2O and extracted with EtOAc. The organic phase was washed with water and brine, dried (Na2SO4) and concentrated. The residue was purified by silica gel column chromatography (DCM/EtOAc, 3:7) followed by trituration in Et2O to afford 11.3 g of the title compound as a white solid: ES-MS: 286 [M+H]+; Rf=0.34 (DCM/EtOAc, 3:7).

Provenance & Evidence