Ring-opening polymerization of ε-caprolactone by lithium piperazinyl-aminephenolate complexes: synthesis, characterization and kinetic studies
Bibliographic record
Abstract
A series of lithium complexes were prepared from 2(N-piperazinyl-N'-methyl)-2-methylene-4-R'-6-R-phenols ([ONN](RR')) and characterized through elemental analysis, (1)H and (13)C{(1)H} NMR spectroscopy, and X-ray crystallography. Treatment of the ligands with n-butyllithium afforded {Li[ONN](RR')}(3) [R = Me, R' = (t)Bu, (1); R = R' = (t)Bu (2); R = R' = (t)Am, (3), (t)Am = C(CH(3))(2)CH(2)CH(3)], with trimetallic structures in the solid-state as shown by single-crystal X-ray diffraction. The reactivity of these complexes in the ring-opening polymerization of ε-caprolactone (ε-CL), as well as the influences of monomer concentration, monomer/Li molar ratio, polymerization temperature and time, was studied. Rates of polymerization were first order with respect to both monomer and lithium concentrations, and activation energies for the reactions were determined. MALDI-TOF MS analysis revealed that transesterification had occurred during the polymerization.
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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 | 0.001 |
| 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".