1-(1-Ethyl-propenyl)-3-trimethylsilyoxy-2-aza-1,3-butadiene → 6-Chloro-4'-(3-chloro-phenyl)-2'-(1-ethyl-propenyl)-2,3-dihydro-2,6'-dioxo spiro[indole-3,3'-piperidine] 1-methoxyethyl trimethylsilane

Participants

Reaction Steps

In a manner similar to the method described in example 55b, E/Z-6-chloro-3-(3-chloro-benzylidene)-1-(2-trimethylsilanyl-ethoxymethyl)-1,3-dihydro-indole-2-one (5.4 g, 12.8 mmol) prepared in example 55a was reacted with 1-(1-ethyl-propenyl)-3-trimethylsilyoxy-2-aza-1,3-butadiene (20 g, 95 mmol) prepared in example 66a in toluene (200 mL) to give racemic (2′R,3R,4′S)-6-chloro-4′-(3-chloro-phenyl)-2′-(1-ethyl-propenyl)-2,3-dihydro-2,6′-dioxospiro[indole-3,3′-piperidine]-1-methoxyethyl trimethylsilane as a white gum (Yield 6.1 g, 85%).

Provenance & Evidence