Water-Accelerated Decomposition of Olefin Metathesis Catalysts.

ABSTRACT: Water is ubiquitous in olefin metathesis, at levels ranging from contaminant to cosolvent. It is also non-benign. Water-promoted catalyst decomposition competes with metathesis, even for "robust" ruthenium catalysts. Metathesis is hence typically noncatalytic for demanding reactions in water-rich environments (e.g., chemical biology), a challenge as the Ru decomposition products promote unwanted reactions such as DNA degradation. To date, only the first step of the decomposition cascade is understood: catalyst aquation. Here we demonstrate that the aqua species dramatically accelerate both β-elimination of the metallacyclobutane intermediate and bimolecular decomposition of four-coordinate [RuCl(H₂O)_n(L)(=CHR)]Cl. Decomposition can be inhibited by blocking aquation and β-elimination.

SUBMITTER: Blanco CO 

PROVIDER: S-EPMC9872090 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature