Synthetic investigations on new calixsalens and modified thiacalixarenes
Bibliographic record
Abstract
“Calix”-compounds have “cup”- or “basket”-like shapes which make them attractive synthetic targets for host-guest studies and for many other potential applications. The research described in this thesis deals with two sets of objectives, (a) The synthesis and characterization of new generation of calixsalens; and (b) The study of the reactions of thiacalix[4]arene 1,3-bistriflate and the chemistry of thiacalix[2]phenoxathiins. -- Calixsalens are dimeric compounds in which the two salen units are connected by methylene, ethylene or sulfonyl linking groups, and are usually prepared under Schiff-base macrocyclizations of bis-salicylaldehydes with diamines. Chiral Mn(III)-calixsalen complexes have been designed to serve as enantioselective epoxidation catalysts which act via a host-guest catalytic mechanism in which reactants can be included within the chiral cavities of the new complexes. New calixsalen ligands with large (chiral) cavities were synthesized by incorporating new linking groups between the two salen units. Modified low mol% Pd Suzuki conditions efficiently produced the desired targeted bis-salicylaldehydes which were used as the precursors for the desired calixsalen compounds. -- The second part of this thesis describes the attempted modification of thiacalix[4]arene to form the narrow rim-functionalized arylethynyl derivative, using the Sonogashira reaction. However, the reactions employed produced instead an unexpected new pheoxathiin product under Cu(I)-catalyzed conditions. A host-guest complexation study was conducted with the new phenoxathiin and its de-tert-butylated analogue and both were shown to be moderate receptors for Ag⁺ and Hg²⁺ ions but not at all with the neutral Ca₆₀ and Ca₇₀ fullerenes.
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 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 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.002 |
| 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".