Synthesis of Fused Nitrogen Containing Heterocycles via Cascade Reactions
Bibliographic record
Abstract
The synthesis of fused nitrogen heterocycles has been investigated. Chapter 1 describes the synthesis of quinolones through a copper catalyzed amide coupling to ortho acetyl aryl halide followed by an aldol condensation that produces the quinolone in modest to good yields. The reaction works well with lactam partners and leads to tricyclic ring systems. Chapter 2 describes\nthe synthesis of 8 membered enamide rings through a [3,3] sigmatropic rearrangement ring expansion of N-vinyl β-lactams. The N-vinyl β-lactams also undergo a 6π electrocyclization following the [3,3] sigmatropic rearrangement to furnish amino cyclobutanes. Previously reported amino cyclobutanes have been made using [2+2] photocycloaddition and resulted in a\nmixtures of diastereoisomers. Our method produces the amino cyclobutanes in good to high yields and with excellent levels of diastereoselectivity. Chapter 3 describes the synthesis and applications of reduced hydantoins from aziridine aldehydes and isocyanates. The resulting heterocycles contain an aziridine ring fused to a 5 membered urea. We also demonstrate that the\nreduced portion of the hydantoin, namely the hydroxyl group, can undergo further displacement with β-ketoesters similar to iminium ion chemistry.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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) | 0.006 | 0.001 |
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".