New Iminophosphonamide Chromium(II) Complexes as Highly Active Polymer-Free Ethylene Oligomerization Catalysts
Bibliographic record
Abstract
The reactions of the deprotonated form of cis -{[(μ-N)( t -Bu)] 2 PN(H)( o -OMeC 6 H 4 )] 2 } ( a ) with either CrCl 2 (THF) 2 or CrCl 3 (THF) 3 afforded the corresponding dimeric Cr(II) and monomeric Cr(III) complexes { cis- [(μ-N)( t -Bu)] 2 [PN( o -MeOC 6 H 4 )] 2 Cr} 2 ( 1a ) and cis- [(μ-N)( t -Bu)] 2 [PN-2-MeOC 6 H 4 ] 2 CrCl ( 2a ). By replacing the ligand’s o -OMeC 6 H 4 groups with less-crowded CH 2 CH 2 N( i -Pr) 2 functionalities and reacting the deprotonated form of cis -{[(μ-N)( t -Bu)] 2 [PN(H)CH 2 CH 2 N( i -Pr) 2 )] 2 } ( b ) with CrCl 2 (THF) 2, the dimetallic, divalent { cis- [(μ-N)( t -Bu)] 2 [PNCH 2 CH 2 N( i -Pr) 2 )] 2 Cr} 2 ( 1b ) was obtained in crystalline form. Upon activation with MAO, both 1a and 1b afforded highly active, polyethylene-free ethylene oligomerization catalysts. Complex 2a is instead catalytically inactive.
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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 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.109 | 0.001 |
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; both teacher heads agree on what is shown here.
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".