Title : With one catalyst in multiple steps in One-pot Fashion - Sequentially palladium-catalyzed processes for the synthesis of functional heterocycles
One-pot reactions, if conducted in a consecutive, sequential or domino fashion, promise a highly efficient and efficacious synthetic access to many functional molecules of interest. In particular, heterocyclic systems are interesting due to their vast spectrum of applications. Transition metal catalyzed multi-component sequences have recently gained a considerable interest since they enable transformations with high tolerance of functional groups. Over the years we have established Pd-catalyzed entries to ynones, diynones, diynes, enals, enones, and boronates, which are valuable intermediates for in situ transformation into complex molecules in a one-pot fashion. Likewise, sequentially Pd-catalyzed processes have opened new avenues to one-pot syntheses of numerous classes of heterocyclic frameworks. Most interestingly, in sequentially Pd-catalyzed processes the same catalyst source is operative a second time without further catalyst addition. This one-pot methodological concept is most elegantly applied to the syntheses of various classes of functional heterocycles, ranging from functional chromophores and electrophores to luminophore, and as a key step in very concise syntheses of marine alkaloids, kinase inhibitors and anti-infectiva. By virtue, concise accesses to substance libraries of interest in organic materials and life sciences are efficiently enabled.
- Multicomponent reactions allow for assembling relatively complex structures in a concise and efficient way.
- Substance libraries are readily obtained with avoiding multi-step and multi-work up operations.
- Enhanced lead finding can be done in a one-process more efficaciously and this is always superior to multi-operation sequences.
- The conceptual approach is a reactivity-based concatenation of quite various reactivity of the underlying functionalities in a single reaction vessel to allow for a concise sequence.
- The combination of catalytic and even catalyst economic one-pot methodologies with targeting functional molecules of interest (chromophores, electrophores, fluorophores, pharmacophores) provides novel structures but simultaneously represents a greener approach to efficient chemistry, which is definitively in the focus at times of climate change and shrinking resources.