Methanol → racemic (2'R,3R,4'S)-6-chloro-4'-(3-cyano-phenyl)-2'-(1-methylene-propyl) spiro[3H-indole-3,3'-piperidine]-2,6'(1H)-dione

Participants

Reaction Steps

E/Z-3-(6-Chloro-2-oxo-1,2-dihydro-indol-3-ylidenemethyl)-benzonitrile (280 mg, 1 mmol) prepared in example 134a was heated with 1-(1-methylene-propyl)-3-trimethylsilyoxy-2-aza-1,3-butadiene freshly prepared in example 80a (2.06 g, 10.5 mmol) in toluene (20 mL) in a sealed tube at 135° C. for 1 h, then cooled to room temperature. Methanol (80 mL) was added, and the mixture was filtered through a short pad of celite. The filtrate was concentrated, the residue was purified by chromatography (EtOAc) to give racemic (2′R,3R,4′S)-6-chloro-4′-(3-cyano-phenyl)-2′-(1-methylene-propyl)spiro[3H-indole-3,3′-piperidine]-2,6′(1H)-dione as a solid (180 mg, 35%).

Provenance & Evidence