Development of environmentally friendly organometallic catalysis for drug discovery and its application to heterocyclic chemistry

Abstract

Two new catalysts, ruthenium hydride with a nitrogen-containing heterocyclic carbene (A) and an organopalladium catalyst supported on a sulfur-terminated semi-conductor, gallium arsenide (001) (B) were discovered. Both catalysts are environmentally benign, because A can yield indole derivatives with good atom economy, and B can catalyze the Mizoroki-Heck reaction more than 10 times with only trace amounts of leached palladium (ppb level). Substituted 1,2-dihydroquinoline, indole and 3-methylene-2,3- dihydroindole were also prepared selectively from the common starting material, N-allyl-o-vinylaniline, and catalyst by slight modification of the reaction conditions. These procedures address an important issue in diversity-oriented synthesis. These methods utility were demonstrated by application to biologically active natural products synthesis. © 2007 The Pharmaceutical Society of Japan.