(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 → N-(allyloxy)-N-((3R,6S)-5-(2-((tert-butyldimethylsilyl)oxy)ethyl)-6-(((tert-butyldimethylsilyl)oxy)methyl)-1,2,3,6-tetrahydropyridin-3-yl)-2-nitrobenzenesulfonamide

Participants

Reaction Steps

To a solution of (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 (Intermediate 282, 7.5 g, 10.11 mmol) in DCM (100 mL) at room temperature was added zinc bromide (6.83 g, 30.32 mmol). The reaction mixture was stirred overnight at room temperature. Another equivalent of zinc bromide was added and the reaction mixture was stirred for another 24 hours. The reaction mixture was diluted with DCM and saturated sodium bicarbonate was added. The biphasic mixture was filtered through celite to remove the solids and the layers were separated. The organics were washed once with brine, dried over magnesium sulfate, filtered and concentrated to afford an orange oil (6.49 g, 100%).

Provenance & Evidence