1208117-75-2Relevant academic research and scientific papers
Highly enantioselective intramolecular cyanoamidation: (+)-horsfiline, (-)-coerulescine, and (-)-esermethole
Reddy, Venkata Jaganmohan,Douglas, Christopher J.
supporting information; experimental part, p. 952 - 955 (2010/06/15)
(Figure Presented) The first asymmetric cyanoamidation with synthetically useful enantioselectivlty (ee up to 99%) to produce 3,3-disubstltuted oxindoles Is reported. Palladium catalysts with chi ral phosphoramldite ligands activate the cyanoformamide C-CN bond, which is subsequently functionalized with a tethered alkene to give all-carbon quaternary stereocenters. The use of the N,N-(i-Pr)2 derivative of octahydro-MonoPhos allowed the production of oxindoles with high enantioselectivlties. Cyanoformamides bearing free N-H groups are now tolerated, potentially allowing protecting-group-free synthesis. Oxindole products of cyanoamidation are rapidly transformed into (+)-horsfiline, (-)-coerulescine, and (-)-esermethole.
Catalytic C-CN activation and asymmetric cyanoamidation of alkenes: Total syntheses of (+)-horsfiline, (-)-coerulescine, and (-)-esermethole
Reddy, Venkata Jaganmohan,Douglas, Christopher J.
experimental part, p. 4719 - 4729 (2010/08/06)
The detailed study of Pd-catalyzed asymmetric cyanoamidation is reported. Excellent enantioselectivities are attributed to a chiral phosphosphoramidite ligand synthesized in one step from the commercially available materials. Cyanoamidation substrates are easy to prepare from the corresponding anilines. The 3,3-disubstituted oxindole products bear all-carbon quaternary stereocenters and contain a nitrile and an amide, which are valuable functional handles for the synthesis of many indole-containing natural products. Cyanoamidation tolerates free N-H groups, as demonstrated by the successful use of cyanoamidation in the syntheses of (+)-horsfiline and (-)-coerulescine.
