Phenylene- and Biphenylene-Bridged Bis-Imidazolylidenes of Palladium. Influence of the Presence of Pyrene Tags on the Catalytic Activity of the Complexes
Bibliographic record
Abstract
A series of dimetallic complexes with N-heterocyclic carbene ligands with formally identical stereoelectronic properties have been obtained and fully characterized. The dimetallic complexes were bridged by bis-imidazolylidenes, with different spacers (phenylene and biphenylene). The N substituents were methyl or methylpyrene groups. The related monometallic complexes were also obtained. The catalytic properties of the complexes were tested in the acylation of aryl halides with hydrocinnamaldehyde and in the Suzuki–Miyaura coupling between aryl halides and arylboronic acids. In general, the dimetallic complexes display better activities than the monometallic analogues. The results also indicate that those complexes with pyrene groups at the N substituents display better catalytic activities than those with N -methyl groups. These observations are interpreted as a consequence of the π stacking interaction between the substrates and the pyrene groups in the pyrene-containing catalysts, which may provide some beneficial catalytic properties. The addition of a catalytic amount of pyrene to the Suzuki–Miyaura coupling reactions results in a partial inhibition of the activities of the complexes with the pyrene substituents, while the activity of the complexes with the N -methyl groups is not affected.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".