Triphenylphosphine → (2S,5R)-tert-butyl 5-(N-(allyloxy)-2-nitrophenylsulfonamido)-3-(2-((tert-butyldimethylsilyl)oxy)ethyl)-2-(((tert-butyldimethylsilyl)oxy)methyl)-5,6-dihydropyridine-1(2H)-carboxylate

Participants

Reaction Steps

To a solution of (2S,5S)-tert-butyl 3-(2-((tert-butyldimethylsilyl)oxy)ethyl)-2-((tert-butyldimethylsilyl)oxy)methyl)-5-hydroxy-5,6-dihydropyridine-1(2H)-carboxylate (Intermediate 281, 7.33 g, 14.61 mmol) in toluene (100 mL) at room temperature was added triphenylphosphine (4.58 g, 17.53 mmol), N-(allyloxy)-2-nitrobenzenesulfonamide (3.77 g, 14.61 mmol) and diisopropyl azodicarboxylate (3.45 mL, 17.53 mmol). The reaction mixture was stirred overnight at room temperature then concentrated. The resulting oil was triturated with hexane and filtered to remove triphenylphosphine oxide. The filtrate was concentrated onto silica gel. Silica gel chromatography (0%-20% ethyl acetate/hexanes) afforded the title compound (7.5 g, 69.2%) as a light yellow oil.

Provenance & Evidence