Carbon–Carbon Bond Formation: The Petrov Synthesis of Combretastatin A-4
Bibliographic record
Abstract
Janine Cossy of ESPCI Paris (Org. Lett. 2011, 13, 4084) and Yasushi Obora of Kansai University (Chem. Lett. 2011, 40, 1055) independently developed conditions for the “borrowed hydrogen” condensation of acetonitrile with an alcohol 1 to give the nitrile 2. Akio Baba of Osaka University showed (Angew. Chem. Int. Ed. 2011, 50, 8623) that a ketene silyl acetal 4 could be condensed with a carboxylic acid 3 to give the β-keto ester 5. Timothy W. Funk of Gettysburg College found (Tetrahedron Lett. 2010, 51, 6726) that the cyclopropanol 6, readily prepared by Kulinkovich condensation of an alkene with an ester, opened with high regioselectivity to give the branched ketone 7. In an elegant application of C–H functionalization, Yong Hae Kim of KAIST and Kieseung Lee of Woosuk University added (Tetrahedron Lett. 2011, 52, 4662) the acetal 9 in a conjugate sense to 8 to give 10. Hitoshi Kuniyasu and Nobuaki Kambe of Osaka University devised (Tetrahedron Lett. 2010, 51, 6818) conditions for the Pd-catalyzed carbonylation of a silyl alkyne 11 to the ester 12 with high geometric control. Dennis G. Hall of the University of Alberta also observed (Chem. Sci. 2011, 2, 1305) good geometric control in the rearrangement of the vinyl carbinol 13 to the alcohol 14. Takashi Tomioka of the University of Mississippi condensed (J. Org. Chem. 2011, 76, 8053) the anion 16, prepared in situ from lithio acetonitrile and 1-iodobutane, with the aldehyde 15 to give a nitrile, which was carried onto the aldehyde 17, again with good control of geometry. Bruce H. Lipshutz of the University of California, Santa Barbara established (Org. Lett. 2011, 13, 3818) conditions for the Negishi coupling of an alkenyl halide 18 to give 20 with retention of alkene geometry. Daesung Lee of the University of Illinois, Chicago found (J. Am. Chem. Soc. 2011, 133, 12964) that a Pt catalyst rearranged a silyl cyclopropene 21 to the allene 22. Jan Deska of the Universität zu Köln prepared (Angew. Chem. Int. Ed. 2011, 50, 9731) the enantiomerically enriched allene 25 by lipase-mediated esterification of the prochiral 23.
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 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.002 |
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".