Domino and Other Olefin Metathesis Reaction Sequences

Ring-closing-metathesis-based synthesis of annellated coumarins from 8-allylcoumarins

“…As a method to circumvent notoriously difficult acrylate RCM steps we [45] and others [67] have developed an assisted tandem catalytic [68] RCM/allylic oxidation sequence. Such tandem sequences are characterized by the combination of two mechanistically distinct catalytic reactions in a defined order, which proceed with a single precatalyst that undergoes a transformation in situ upon addition of a suitable reagent, a “chemical trigger” [69]. In the case of the RCM/allylic oxidation sequence tert -butyl hydroperoxide is added after completion of the metathesis reaction, which most likely induces a conversion of the metathesis active Ru–carbene species to a Ru(IV)–oxo species.…”

Editorial of Special Issue Ruthenium Complex: The Expanding Chemistry of the Ruthenium Complexes

“…Ru-catalyzed enyne metathesis (EYRCM) provided an elegant and productive way to obtain small, medium and large cyclic molecules [255]. Numerous tandem metathesis protocols (RCM-CM, RCM-RCM, and RCM-ROM-CM), as well as related processes (C–C coupling, cyclopropanation, cyclizations, and polymerizations) facilitated the synthesis of complex organic molecules, intermediates for fine chemicals, bioactive natural products, macrocyclic or polycyclic structures, functional polymers and supramolecular architectures [256,257,258,259,260,261,262,263,264]. Intricate scaffolds for pharmaceuticals and agrochemicals have been accessed by these advanced strategies [265,266,267].…”

Influência Do Impedimento Estérico De Ligantes Ancilares Em Complexos a Base De Ru Aplicados Em Metáteses Do Álcool E Acetato Cinamílicos

“…Uma das grandes vantagens é possibilitar a obtenção de moléculas insaturadas através da reorganização ou troca dos elementos que formam a dupla ligação, tendo em vista que o preparo delas por outro método seria muito difícil. 1,2 Essa reação consiste em uma alternativa atraente devido à grande variedade de materiais de partida e atividade dos catalisadores, 3,4 sendo amplamente utilizada em sínteses orgânicas, na química medicinal e na química de polímeros. 5,6 Muitos complexos têm sido usados em metátese de olefinas, no entanto, vários metais de transição são inapropriados para serem utilizados como catalisadores nessas reações.…”