Chromium Amino-bis(phenolate) Complexes as Catalysts for Ring-Opening Polymerization of Cyclohexene Oxide
Bibliographic record
Abstract
The chromium(III) amino-bis(phenolate) “ate” complex, {Na[CrCl2L1]}, 1, where L1 = 6,6′-((1,4-diazepane-1,4-diyl)bis(methylene))bis(2,4-di-tert-butylphenolato) and its derivatives 2–4 (where the phenolate substituents and the diamino linker were varied) were prepared. Single crystals obtained by recrystallization of 1 were shown by X-ray diffraction to be a related octahedral complex, 1′, where one of the O-donors in 1′ is protonated, resulting in a monoanionic ligand and affording a neutral Cr(III) dichloride complex. The ligand [L1] chelates in a meridional fashion and anionic chloride donors reside in a trans axial orientation. Cr(III) amino-bis(phenolate) complexes 1–4 showed good activity toward ring-opening polymerization (ROP) of cyclohexene oxide (CHO) without the use of an added cocatalyst, producing high-molecular weight poly(cyclohexene oxide) where 1 was the most active catalyst. Arrhenius data obtained for the ROP of CHO using 1 revealed an activation barrier of 64.0 ± 9.8 kJ mol–1 and the nonlinear polymer molecular weight growth versus conversion relationship suggests a step-growth polymerization mechanism.
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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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| 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".