合成路线1

Heck coupling of 2-bromo-6-fluoroaniline (I) with methyl acrylate (II) by means of Pd(oAc)2, (o-tol)3P and Et3n in refluxing acetonitrile yields the (E)-cinnamate (III), which is then treated with PPh3 in the presence of CCl4 and Et3n in acetonitrile to give the iminophosphorane (IV). Compound (IV) is then condensed with 2-methoxy-5-(trifluoromethyl) phenyl isocyanate (V) [prepared by treatment of 2-methoxy-5-(trifluoromethyl)aniline (VI) with diphosgene in the presence of proton sponge] in CH2Cl2 to provide the carbodiimide (VII). Cyclocondensation of carbodiimide (VII) with 1-(3-methoxyphenyl)-piperazine (VIII) in the presence of Sio2 in refluxing CH2Cl2 affords the 3,4-dihydroquinazoline derivative (IX) (1), which is then subjected to ester hydrolysis with naoH in H2o/dioxane to produce the racemic carboxylic acid (X) . Finally, racemate (X) is resolved through chiral HPLC .
In an alternative procedure, chlorination of the dihydroquinazolinone derivative (XI) with PoCl3 and DBU in refluxing chlorobenzene, followed by coupling of the resulting 2-chloro-3,4-dihydroquinazoline (XII) with 1-(3-methoxyphenyl)piperazine (VIII) in the presence of DBU in refluxing dioxane produces the 3,4-dihydroquinazoline derivative (IX). Resolution of the racemic ester (IX) using di-p-toluoyl-D-tartaric acid in EtoAc provides the corresponding (S)-enantiomer (XIII), which is finally hydrolyzed with naoH in H2O/dioxane .