Toward the ideal synthesis. New transition metal-catalyzed reactions inspired by novel medicinal leads

Studies in our laboratory are directed at the advancement of synthesis, biology, and medicine. This lecture will focus on new transition metal-catalyzed reactions that have been inspired by biologically potent targets such as phorbol and Taxol ® and by the more general interest in producing syntheses that are concise, efficient, cost- and resource-effective, envi- ronmentally benign, quick, and simple to conduct—in essence, ideal. A special emphasis in our program is placed on new transition metal-catalyzed reactions that, in the absence of cat- alyst, would be forbidden or difficult to achieve. We have thus far reported the first examples of intramolecular metal-catalyzed (4+2), (5+2), and (4+4) cycloadditions, reactions that pro- duce 6-, 7-, and 8-membered rings, respectively. Recent advances in our (5+2) cycloaddition studies will be presented, including new catalysts for relative and absolute stereochemical control. We will also describe recyclable catalysts that can be used in water, thereby mini- mizing cost and environmental concerns about solvent waste streams. New multicomponent reactions will also be presented. Finally, we will report a new (6+2) cycloaddition that pro- duces an 8-membered ring.