Trifluoroacetic acid → 3-Chloro-4-hydroxybenzoic Acid {4-[2-(4-Benzylpiperazin-1-yl)ethoxy]-2-methoxybenzylidene}hydrazide

Participants

Reaction Steps

This compound was prepared analogously to the compound described in the previous example starting from resin bound 3-chloro-4-hydroxybenzoic acid hydrazide (resin—[building block 1]) (2 g, ˜2 mmoles), 4-(2-bromoethoxy)-2-methoxybenzaldehyde ([building block 2]) (0.73 g, 1.5 equivs.), and 1-benzylpiperazine ([building block 3]) (3.3 g, 10 equivs.). After cleavage with 50% trifluoroacetic acid, the residue (1.4 g) was dissolved in 2-propanol (50 ml) and concentrated to 20 ml. The mixture was allowed to stand at 5° C. for 1 h and filtered. The mother liquor was concentrated in vacuo and the residue was purified by column chromatography on silica gel (20 g) eluting with a mixture of methanol and dichloromethane (1:9). This afforded 0.98 g of the title compound.

Provenance & Evidence