Z-6-chloro-3-(3-chloro-benzylidene)-2-oxo-2,3-dihydro-indole-1-carboxylic acid tert-butyl ester → racemic (2'R,3R,4'S)-6-chloro-4'-(3-chlorophenyl)-2,3-dihydro-2'-(2-methylphenyl)-2,6'-dioxospiro[indole-3,3'-piperidine]-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

In a manner similar to the method described in example 4c, E/Z-6-chloro-3-(3-chloro-benzylidene)-2-oxo-2,3-dihydro-indole-1-carboxylic acid tert-butyl ester (1 g, 2.6 mmol) prepared in example 24a was reacted with 1-(2-methylphenyl)-3-trimethylsilyoxy-2-aza-1,3-butadiene (3.3 g, 14.1 mmol) prepared in example 17a, in toluene to give racemic (2′R,3R,4′S)-6-chloro-4′-(3-chlorophenyl)-2,3-dihydro-2′-(2-methylphenyl)-2,6′-dioxospiro[indole-3,3′-piperidine]-1-carboxylic acid tert-butyl ester as a white foam (Yield: 0.92 g, 65%).

Provenance & Evidence