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Abstract Tethered tungsten‐alkylidenes bearing azoimido ligands (M≡Nγ‐Nβ=NαR) are synthesized, characterized, and tested as initiators for ring expansion metathesis polymerization (REMP). While these ligands are typically unstable and prone to dinitrogen loss, this work demonstrates that tethered alkylidene complexes bearing azoimido ligands are stable enough to be REMP initiators. Moreover, they are more efficient, long‐lived, and stereoselective than their corresponding imido derivatives (M≡NR). Density Functional Theory (DFT) analysis of the azoimido complexes provides insight into their unusual stability.
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Hydrogenative Catalysis with Three‐Coordinate Zinc Complexes Supported with PN Ligands is Enhanced Compared to PNP Analogs
Abstract This work details the synthesis, characterization, and catalytic activity of reactive low‐coordinate organozinc complexes. The complexes activate hydrogen and they appear to be more active in hydrogenation of ketones and imines than their tridentate pincer analogs. This is thought, in part, to be due to the lack of trailing third phosphorus arm present in previous work. DFT computations reveal a sigma‐bond metathesis mechanism is comparable to an alternative aromatization/dearomatization metal‐ligand cooperative mechanism.
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- PAR ID:
- 10368833
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 28
- Issue:
- 40
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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