A One-Pot Synthesis of Functionalized Tetrahydro-4HChromenes and Tetrahydro-4H-Thiopyrans Derivatives
Bibliographic record
Abstract
An efficient approach for the synthesis of functionalized tetrahydro-4H-chromenes 3a-c and tetrahydro-4H-thiopyran 3d-e derivatives moderate to high yields have been achieved via a addition-cyclization reaction of , -Unsaturated cyanoesters 1a-c with dimedone 2p or 1, 3-cyclohexandione 2q in presence of sodium ethoxide and Benzaldehyde with 2-propanol in presence of ammonium sulphide respectively. This methodology differs from the previous classical methods in its simplicity and ready availability of the catalyst. The structures of the compounds 3a-e were confirmed by their ultraviolet, infrared, 1 H NMR, 13 C NMR and elemental analyses.
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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 | 0.001 | 0.002 |
| 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 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".