Triethylamine → 5-[4-[6-(4-n-Hexylaminophenoxy)-1-methyl-1H-benzimidazol-2-ylmethoxy]benzyl]thiazolidine-2,4dione

Participants

Reaction Steps

A mixture of t-butyl N-[2-amino-5-(4-t-butoxycarbonyl-n-hexylaminophenoxy)phenyl]-N-methylcarbamate (4.10 g), 4-(2,4-dioxothiazolidin-5-ylmethyl)phenoxyacetic acid (2.81 g), diethyl cyanophsphonate (1.63 g), triethylamine (1.01 g) and anhydrous tetrahydrofuran (100 ml) was stirred at ambient temperature for 28 hours. The reaction mixture was concentrated and the residue was partitioned between ethyl acetate and water. The ethyl acetate layer was dried over anhydrous sodium sulfate and concentrated. A mixture of the residue and 4N hydrogen chloride/dioxane (50 ml) was stirred at ambient temperature for 66 hours. Water was added to the reaction mixture and the mixture was neutralized with sodium bicarbonate and extracted with ethyl acetate. The ethyl acetate was dried over anhydrous sodium sulfate and evaporated. The residue was purified by chromatography on a silica gel column using n-hexane/ethyl acetate=2/3 as the eluant to give the title compound (2.89 g).

Provenance & Evidence