Transition metal-free one-pot cascade synthesis of 7-oxa-2-azatricyclo[7.4.0.02,6]trideca-1(9),10,12-trien-3-ones from biomass-derived levulinic acid under mild conditions
Bibliographic record
Abstract
An efficient, environmentally benign, transition-metal free, tandem C-N, C-O bond formation reaction is developed for the synthesis of tricyclic 7-oxa-2-azatricyclo[7.4.0.0(2,6)]trideca-1(9),10,12-trien-3-ones and their homologs from easily available starting materials, including renewable levulinic acid, a keto acid. The reaction of keto acids with methyl chloroformate and variously substituted o-aminobenzyl alcohols using triethylamine as a base in toluene at room temperature gave good to excellent yields. This newly developed protocol was successfully utilized for the synthesis of a variety of polycyclic 7-oxa-2-azatricyclo[7.4.0.0(2,6)]trideca-1(9),10,12-trien-3-ones and related compounds.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.027 | 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".