Highly substituted indole library synthesis by palladium-catalyzed coupling reactions in solution and on a solid support.
3-Iodoindoles have been synthesized by the iodocyclization of N,N-dialkyl-o-(1-alkynyl)anilines, obtained by the Pd/Cu catalyzed coupling of terminal acetylenes with N,N-dialkyl-o-iodoanilines. These 3-iodoindoles undergo palladium-catalyzed Sonogashira and Suzuki coupling reactions to yield 1,2,3-trisubstituted indoles. These reactions have been applied to parallel library synthesis utilizing commercially available terminal acetylenes and boronic acids. The aforementioned chemistry has also been carried out on a chlorinated Wang resin as a solid support, affording 1,2,3,5-tetrasubstituted indoles after cleavage from the support. A diverse 42-member library of highly substituted indoles has been synthesized.
Worlikar
Shilpa A
SA
Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
Neuenswander
Benjamin
B
Lushington
Gerald H
GH
Larock
Richard C
RC
D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D020650:Combinatorial Chemistry Techniques; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010165:Palladium / Q000737:chemistry*; D012996:Solutions
D007211:Indoles; D012996:Solutions; D010165:Palladium