反应详情

A solution of tert-butyl 3-(2-chloro-3-((4-(2-ethylthiazole-4-carbonyl)-1-oxa-4,9-diazaspiro[5.5]undecan-9-yl)methyl)phenethoxy)propanoate (limiting reagent) (step d) in DCM (2.8 volumes) was cooled to 5° C. Trifluoroacetic acid (10 molar equivalents) was added over 20 min (exotherm to 15° C.). The reaction mixture was warmed to ambient and stirred for 18 hr, Toluene (3 volumes) was added and the mixture was evaporated. The resulting gum was triturated with toluene (2×1.5 volumes) and evaporated to give a brown gum. Yield: 200% of theoretical. (carried through crude—NMR assay shows ˜45% by weight purity with remaining weight due to TFA trapped in the gum)

1. temperatureThe reaction mixture was warmed to ambient and
2. customthe mixture was evaporated
3. customThe resulting gum was triturated with toluene (2×1.5 volumes)
4. customevaporated
5. customto give a brown gum