合成路线1

The nitration of 2-(3,4-dichlorophenyl)acetic acid (I) with HNO3 and H2SO4 gives 2-(4,5-dichloro-2-nitrophenyl)acetic acid (II), which is treated with refluxing SOCl2 to yield the corresponding acyl chloride (III). The condensation of (III) with bis(trimethylsilyl)acetylene (IV) by means of AlCl3 in dichloromethane affords 1-(2-nitro-4,5-dichlorophenyl)-4-(trimethylsilyl)-3-butyn-2-one (V), which is submitted to a reductive cyclization by means of Fe/AcOH to provide 5,6-dichloro-2-ethynyl-1H-indole (VI) after desilylation with NaOH in methanol. The reaction of (VI) with (Bu3Sn)BuCuCNLi2 gives 5,6-dichloro-2-[2(E)-(tributylstannyl)vinyl]-1H-indole (VII), which is condensed with methyl 3-bromo-2-methoxy-2-propenoate (VIII) by means of Pd(PPh3)4 in hot THF to yield the pentadienoic ester (IX). The hydrolysis of (IX) with LiOH in MeOH affords the corresponding carboxylic acid (X), which is finally condensed with the amine (XI) by means of EDC and HOBT in dichloromethane to provide the target amide.