Diisopropylethylamine → (R)-3-(2-chloro-4-nitroimidazol-1-yl)-2-hydroxy-2-methylpropyl 4-(4-chlorobenzyl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

(R)-2-Chloro-1-(2,3-dihydroxy-2-methyl)propyl-4-nitroimidazole prepared in Example 10 (2.28 g, 9.66 mmol), N,N-diisopropylethylamine (2.81 ml, 16.10 mmol) and 4-dimethylaminopyridine (0.20 g, 1.61 mmol) were added to a suspension of 4-(4-chlorobenzyl)piperazine-1-carbonylchloride (2.20 g, 8.05 mmol) in toluene (30 ml) followed by stirring 100° C. for 3 hours. The reaction mixture was diluted with ethyl acetate, washed with water, dried over magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methylene chloride/ethyl acetate=9/1) to afford (R)-3-(2-chloro-4-nitroimidazol-1-yl)-2-hydroxy-2-methylpropyl 4-(4-chlorobenzyl)piperazine-1-carboxylate (1.82 g, yield 48%) as a yellow oil.

Provenance & Evidence