C<sub>19</sub> quassinoid model studies: Preparation of <i>trans</i>-perhydroindans via a vinylogous Mukaiyama aldol free-radical cyclization route
Bibliographic record
Abstract
Aldehyde 9 was prepared in 5 steps from 3,5-dimethylbenzoic acid. Treatment of 9 with ketene acetals 10 and 19 and titanium tetrachloride gave free-radical cyclization substrates 11 and 20 in 67% and 51% yields, respectively. Tri-n-butylstannane-mediated cyclization of 11 and 20 gave trans-perhydroindans 14 and 21 in 60% and 63% yields, respectively. The relationship of these studies to an approach to C 19 quassinoids is discussed.Key words: vinylogous Mukaiyama aldol reaction, free-radical cyclization, trans-perhydroindans, C 19 quassinoids, 1,2-asymmetric induction.
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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) | 0.000 | 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".