Novel synthesis of 2-naphthol Mannich bases and their NMR behaviour
Bibliographic record
Abstract
A novel two-step procedure involving the formation of 1-arylidene-2-tetralones from 2-tetralone and subsequent Michael addition of a cyclic secondary amine on the alkenone followed by in situ aerial oxidation was developed to produce 2-naphthol Mannich bases. A simple microwave-assisted one-pot synthesis of 2-naphthol Mannich bases was also carried out under solvent-free conditions from 2-naphthol and corresponding aldehydes and amines in the presence of p-toluenesulfonic acid. The compounds of this series displayed interesting NMR behaviour. Extensive variable-temperature NMR investigations, including HSQC experiments, are herein reported. NMR results on the conformation in solution phase were found to be consistent with the X-ray crystal structure in the solid state.Key words: Mannich bases, microwave-assisted Mannich reaction, temperature-variable NMR spectroscopy, NMR dynamics, X-ray crystallography.
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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) | 0.002 | 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".