Air-stable 18-electron adducts of Schrock catalysts with tuned stability constants for spontaneous release of the active species
Open Access
- 19 May 2021
- journal article
- research article
- Published by Springer Science and Business Media LLC in Communications Chemistry
- Vol. 4 (1), 1-11
- https://doi.org/10.1038/s42004-021-00503-4
Abstract
Schrock alkylidenes are highly versatile, very active olefin metathesis catalysts, but their pronounced sensitivity to air still hinders their applications. Converting them into more robust but inactive 18-electron adducts was suggested previously to facilitate their handling. Generating the active species from the inactive adducts, however, required a high-temperature Lewis acid treatment and resulted in an insoluble by-product, limiting the practicality of the methodology. Herein, we introduce an approach to circumvent the inconvenient, costly, and environmentally taxing activation process. We show that 18-electron adducts of W- and Mo-based Schrock catalysts with finite stability constants (typically K = 200–15,000 M−1) can readily be prepared and isolated in excellent yields. The adducts display enhanced air-stability in the solid state, and in solution they dissociate spontaneously, hence liberating the active alkylidenes without chemical assistance.Keywords
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