(S,E)-tert-butyl (2,2,3,3,11,11,12,12-octamethyl-7-methylene-4,10-dioxa-3,11-disilatridecan-6-yl)(2-oxopent-3-en-1-yl)carbamate → (S)-tert-butyl 3-(2-((tert-butyldimethylsilyl)oxy)ethyl)-2-(((tert-butyldimethylsilyl)oxy)methyl)-5-oxo-5,6-dihydropyridine-1(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of (S,E)-tert-butyl (2,2,3,3,11,11,12,12-octamethyl-7-methylene-4,10-dioxa-3,11-disilatridecan-6-yl)(2-oxopent-3-en-1-yl)carbamate (Intermediate 279, 10 g, 18.45 mmol) in toluene (400 mL) was purged with nitrogen for 15 minutes. The Hoveyda-Grubbs Catalyst 2nd Generation (2.320 g, 3.69 mmol) was then added. The reaction was heated at 100° C. overnight. Another 0.05 eq of catalyst was added and the reaction mixture was heated at 100° C. for another 2 hours. The reaction mixture was concentrated onto silica gel. Silica gel chromatography (0%-15% ethyl acetate/hexanes) afforded the title compound (8.55 g, 93%) as a light brown oil.

Provenance & Evidence