Origins of Steric Effects in General-Base-Catalyzed Enolization: Solvation and Electrostatic Attraction
Bibliographic record
Abstract
Brønsted plots for general-base-catalyzed enolization of aldehydes and ketones show significant negative deviations for the rates of proton removal by sterically hindered amine bases. The origins of the deviations are not apparent from considerations of interactions at the site of the proton transfer. Contrasting behavior is observed in general-base-catalyzed proton removal from an iminium derivative, N1'-methyl-2-(1-hydroxybenzyl)thiamin (NMHBnT), which shows no deviations from the Brønsted correlation for sterically hindered amine bases. The difference in behavior for these two systems suggests that the steric effects arise from disruption of solvation of the enolate enforced by the electrostatic requirements of the overall process. This interpretation also can account for reduced steric effects for enolization in the presence of metal ions.
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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".