Catalysis of the Hajos—Parrish—Eder—Sauer—Wiechert Reaction by <i>cis</i>‐ and <i>trans</i>‐4,5‐Methanoprolines: Sensitivity of Proline Catalysis to Pyrrolidine Ring Conformation
Bibliographic record
Abstract
Abstract Methanoprolines are found to be catalysts for the Hajos–Parrish–Eder–Sauer–Wiechert reaction.[1] cis‐4,5‐Methanoproline exhibits catalytic ability similar to proline (86% yield, 93% ee), whereas the trans‐4,5‐methanoproline is less selective (67% yield, 83% ee) and shows less acceleration. The reaction was also studied with hybrid density functional theory (B3LYP). The nearly planar cis‐4,5‐methanoproline amine better reflects the planar iminium of the transition states than the pyramidalized trans‐4,5‐methanoproline. This difference in conformation is responsible for the observed higher enantioselectivity and enhanced catalytic behavior of the cis‐4,5‐methanoproline.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".