The Meisenheimer model for predicting the principal site for nucleophilic substitution in aromatic perfluorocarbons — Generalization to include ring-nitrogen atoms and non-fluorine ring substituents
Bibliographic record
Abstract
Our recent simple model for predicting the principal site for nucleophilic substitution in aromatic perfluorocarbons (J. Fluorine Chem. 2005, 126, 727) is generalized to include both ring-nitrogen atoms and non-fluorine ring substituents. The model is based on the relative stabilities of the Meisenheimer complexes as calculated using Hartree–Fock theory with a modest basis set. Calculations on a wide range of fluorine-containing aromatics demonstrate the general applicability of the model; in over 70 systems examined, we found only one where the predicted primary substitution site did not agree with the experimental findings. We demonstrate that criticism by Chambers et al. to the effect that the model is incapable of reproducing experimental substitution patterns, and, in particular, cannot distinguish between the different activating effects of ortho- and para-fluorines, are entirely unfounded. The observed substitution patterns for six reactions involving attack by aniline on perfluoropyridine and various non-fluorine-substituted derivatives, selected by Chambers et al. to highlight the failings of our model, are, on the contrary, accurately predicted by it.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".