Ozone → 2-(4-Amino-3-oxo-1,3,4,5-tetrahydro-benzo[c]azepin-2-yl)-4-methyl-valeric acid, tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

Dissolve 2-(1,3-dioxo-1,3-dihydro-isoindol-2-yl)-3-(2-vinyl-phenyl)-propionic acid, 2-trimethylsilanyl-ethyl ester (2.61 g, 6.19 mmol) in methylene chloride (70 mL) and methanol (75 mL). Cool to −78° C. and treat with ozone until a blue color persists. Purge with nitrogen and add dimethylsulfide (7 mL) and pyridine (0.35 mL). Allow to warm to room temperature gradually overnight. Partition between methylene chloride (100 mL) and water (40 mL). Extract the aqueous with methylene chloride (50 mL), dry (Na2SO4) and purify by silica gel chromatography (2.5:1 hexane/ethyl acetate) to give the title compound as a colorless viscous oil (2.65 g, 100%). Step h: 2-(2-(2-(1,3,-Dioxo-1,3,dihydro-isoindol-2-yl)-2-(2-trimethylsilanyl-ethoxycarbonyl)-ethyl)-benzylamino)-4-methyl-valeric acid, tert-butyl ester.

Provenance & Evidence