Diisopropylethylamine → (S,E)-tert-butyl 6-(4-methoxy-4-oxobut-2-enamido)-2-((2-(trimethylsilyl)ethoxy)carbonyl)hexanoate

Participants

Reaction Steps

To a stirring mixture of (S)-tert-butyl 6-amino-2-((2-(trimethylsilyl)ethoxy)carbonyl)hexanoate (800 mg, 2.31 mmol), monomethyl fumarate (361 mg, 2.77 mmol), DIEA (1.1 mL, 6.93 mmol) in 10 mL acetonitrile was added HATU (1.14 g, 3.00 mmol) in one portion at 0° C. under an inert atmosphere of argon. The resulting reaction mixture was stirred at room temperature for 2 h and then concentrated under reduced pressure. The resulting residue was diluted with EtOAc (50 mL) and washed with brine, dried over Na2SO4, and concentrated under reduced pressure. Purification by silica gel chromatography (EtOAc/pentane) afforded (S,E)-tert-butyl 6-(4-methoxy-4-oxobut-2-enamido)-2-((2-(trimethylsilyl)ethoxy)carbonyl)hexanoate (900 mg, 85%).

Provenance & Evidence