Selenium Dioxide → (S)-2'-Oxo-1',2',6,8-tetrahydrospiro[cyclopenta[g]quinoline-7,3'-pyrrolo[2,3-b]pyridine]-2-carbaldehyde

Participants

Reaction Steps

A mixture of (S)-2-methyl-6,8-dihydrospiro[cyclopenta[g]quinoline-7,3′-pyrrolo[2,3-b]pyridin]-2′(1′H)-one from Step A (1.30 g, 4.31 mmol) and selenium dioxide (718 mg, 6.47 mmol) in dioxane (50 mL) and H2O (5 mL) was heated at reflux for 4 h. The reaction mixture was concentrated to dryness under reduced pressure. The residue was purified by silica gel chromatography, eluting with a gradient of CH2 Cl2:MeOH—100:0 to 90:10. Product-containing fractions were combined, toluene was added, and the mixture was concentrated in vacuo to give the title compound. MS: m/z=316 (M+1).

Provenance & Evidence