1-Methylimidazole → (+/-)-alpha-(4-chlorophenyl)-1-methyl-alpha-(4-nitrophenyl)-1H-imidazole-5-methanol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

n-Buthyl-lithium in hexane (1.6M; 71.6 ml) was added dropwise at −70° C. under N2 flow to a mixture of 1-methylimidazole (0.1146 mol) in THF (195 ml). The mixture was stirred at −70° C. for 30 minutes. Chlorotrietylsilane (0.1146 mol) was added. The mixture was brought slowly to 10° C. and cooled again to −70° C. n-Buthyl-lithium in hexane (1.6M; 71.6 ml) was added dropwise. The mixture was stirred at −70° C. for 1 hour, brought to −15° C. and cooled again to −70° C. A mixture of 4-chlorophenyl-4-nitrophenyl-methanone (0.095 mol) in THF (150 ml) was added dropwise. The mixture was stirred at −70° C. for 30 minutes, hydrolized and extracted with EtOAc. The organic layer was separated, dried, filtered and the solvent was evaporated. The residue was purified by column chromatography over silica gel (eluent: CH2Cl2/CH3OH NH4OH 96/4/0.1). The desired fractions were collected and their solvents were evaporated, yielding 6.5 g (20%) of (±)-α-(4-chlorophenyl)-1-methyl-α-(4-nitrophenyl)-1H-imidazole-2-methanol (interm 12), 8.7 g (26.6%) of (±)-α-(4-chlorophenyl)-1-methyl-α-(4-nitrophenyl)-1H-imidazole-5-methanol (interm 13) and 18 g (53%) of the mixture of intermediate 12 and 13.

Herkunft & Nachweise