Rights statement: Post Print: This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry, copyright ©2017 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/acs.inorgchem.7b01011
Accepted author manuscript, 974 KB, PDF document
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Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
| <mark>Journal publication date</mark> | 21/08/2017 |
|---|---|
| <mark>Journal</mark> | Inorganic Chemistry |
| Issue number | 16 |
| Volume | 56 |
| Number of pages | 11 |
| Pages (from-to) | 9563-9573 |
| Publication Status | Published |
| Early online date | 7/08/17 |
| <mark>Original language</mark> | English |
Michael addition (MA) is one of the most well studied chemical transformation in synthetic chemistry. Here, we report the synthesis and crystal structures of a library of 3d/4f coordination clusters (CCs) formulated as [Zn(II)2Y(III)2L4(solv)X(Z)Y] and study their catalytic properties toward the MA of nitrostyrenes with barbituric acid derivatives. Each CC presents two borderline hard/soft Lewis acidic Zn(II) centers and two hard Lewis acidic Y(III) centers in a defect dicubane topology that brings the two different metals into a proximity of ∼3.3 Å. Density functional theory computational studies suggest that these tetrametallic CCs dissociate in solution to give two catalytically active dimers, each containing one 3d and one 4f metal that act cooperatively. The mechanism of catalysis has been corroborated via NMR, electron paramagnetic resonance, and UV-vis. The present work demonstrates for the first time the successful use of 3d/4f CCs as efficient and high diastereoselective catalysts in MA reactions.