Triphenylphosphine → Ethyl 3-{2-fluoro-4-[[(2-nitrophenyl)sulfonyl](4-{1-[(4-phenyl-1,3-thiazol-2-yl)methyl]butyl}benzyl)amino]phenyl}propanoate

Participants

Reaction Steps

A solution of ethyl 3-(2-fluoro-4-{[(2-nitrophenyl)sulfonyl]amino}phenyl)propanoate (0.686 g, 1.73 mmol), (4-{1-[(4-phenyl-1,3-thiazol-2-yl)methyl]butyl}phenyl)methanol (0.389 g, 1.15 mmol) and triphenylphosphine (0.603 g, 2.30 mmol) in tetrahydrofuran (15 mL) was stirred under ice-cooling, and diethyl azodicarboxylate (40% toluene solution, 1.05 mL, 2.3 mmol) was added. The mixture was allowed to warm to room temperature and stirred for 16 hr. The reaction mixture was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (10%-80% ethyl acetate/hexane) to give ethyl 3-{2-fluoro-4-[[(2-nitrophenyl)sulfonyl](4-{1-[(4-phenyl-1,3-thiazol-2-yl)methyl]butyl}benzyl)amino]phenyl}propanoate as a yellow oil. To a solution of the obtained oil and mercaptoacetic acid (0.291 g, 3.16 mmol) in N,N-dimethylformamide (15 mL) was added lithium hydroxide monohydrate (0.265 g, 6.32 mmol), and the mixture was stirred at room temperature for 2 hr. Ethyl acetate was added to the reaction mixture, and the mixture was washed with saturated aqueous sodium hydrogencarbonate and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (5%-40% ethyl acetate/hexane) to give the title compound (0.420 g, yield 69%, 2 steps) as a colorless oil.

Provenance & Evidence