合成路线图解说明: The intermediate mixed anhydride (V) has been obtained as follows: the condensation of 2-nitroimidazole (I) with methyl 2-bromoacetate (II) by means of NaOMe in methanol gives 2-(2-nitro-1H-imidazol-1-yl)acetic acid methyl ester (III), which is hydrolyzed with NaOH to yield the corresponding acid (IV). Finally, this compound is condensed with isobutyl chloroformate by means of NMM in THF to afford the desired mixed anhydride intermediate (V).
The condensation of 2,2,2-trifluoroacetaldehyde ethyl hemiacetal (VI) with nitromethane (VII) by means of K2CO3 gives 1,1,1-trifluoro-3-nitro-2-propanol (VIII), which is reduced with H2 over RaNi in ethanol to yield 3-amino-1,1,1-trifluoro-2-propanol (IX). Finally, this compound is condensed with the mixed anhydride intermediate (V) by means of NMM in THF to afford the target amide. |