Studies on the stereoselective synthesis of functionalized quaternary stereocenters and E-3-(arylmethylidene)-5-(alkyl/aryl)-2(3H)-Furanones
Bibliographic record
Abstract
An enantioselective synthesis of isolated acyclic quaternary stereocenters was achieved using metal-catalyzed Gosteli-Claisen rearrangements of allyl vinyl ethers. A concise synthesis of 2-t-butoxycarbonyl allyl vinyl ethers by regioselective Petasis methylenation and stereoselective Suzuki-Miyaura cross-coupling reactions of iodoallyl t-butyl oxalates was developed. Ethers with a terminally unsubstituted vinyl group and a terminally disubstituted allyl portion are readily accessible by this method. In addition to the metal-catalyzed Gosteli-Claisen rearrangements, organocatalytic variant of the Gosteli-Claisen rearrangement was investigated. A modular synthesis of several new, chiral cyclic phosphoramide-based, thioureas, formamidines and thiosemicarbazides was developed and these phosphoramides were examined for their ability to catalyze the Gosteli-Claisen rearrangement of a selected allyl vinyl ether. A variety of E-3-(arylidene)-5-(alkyl/aryl)-2(3H)-furanones were synthesized by employing regioselctive addition of -aryl acrylic acids with iodoacetylenes and subsequent intramolecular Heck reaction of Z-acyloxy iodo alkenes. The approach was applied in a formal synthesis of the naturally occurring kinase inhibitor BE-23372M.
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) | 0.001 | 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".