To a solution in dry DMF (20 mL) of bis(4-hydroxyphenyl)methyloximinoacetic acid ethyl ester (0.64 g, 2 mmol), prepared as in step 1, was added cesium carbonate (1.6 g, 5 mmol), the mixture was stirred for 10 mutes, and 2-bromomethyl-7-chloroquinoline (1 g, 4 mmol) was added. After stirring for 18 hours, the mixture was poured into water and the precipitated solid was collected by filtration, washed with water, and dried in vacuo. Chromatography on silica gel (hexane/EtOAC 3:1) afforded bis(4-(7-chloro-2-quinolylmethoxy)phenyl)-methyloximinoacetic acid ethyl ester (1.1 g).
