Mono‐ and Hetero‐Dinuclear Complexes of Janus‐Head NHC Ligands Possessing Backbone Phosphinoyl Groups: the Case of Soft and Hard Metal Centers
Bibliographic record
Abstract
Abstract The synthesis and structures of Rh I and Ir I complexes bearing 4‐phosphinoyl‐ and 4,5‐bis(phosphinoyl)imidazol‐2‐ylidene ligands (NHC P ) is reported. Deprotonation of the corresponding imidazolium hydrogen sulfate salts by KO t Bu in the presence of [M(cod)Cl] 2 afforded complexes of the formula [M(cod)Cl(NHC P )] [ 5a/5b : NHC P = 4‐Ph 2 P(O)‐I i PrMe, 5a : M = Rh, 5b : M = Ir and 7a/7b : NHC P = 4,5‐{Ph 2 P(O)} 2 ‐I n BuMe]. The Rh I complexes 5a and 7a were then converted into [Rh(CO) 2 Cl(NHC P )] 8a and 9a via reaction with carbon monoxide; the average CO stretching frequencies [ 8a : $\tilde {\nu}$ (CO) av = 2036 cm –1 and 9a : $\tilde {\nu}$ (CO) av = 2038.4 cm –1 ] led to the conclusion that mono‐ and bis‐functionalized NHC P s act as relatively weaker donors than backbone unsubstituted NHC. A first examination of Janus‐head ligand properties of complex 7a revealed that reaction with TiCl 4 afforded hetero‐dinuclear 10a , a′ as a mixture of isomeric monodentate phosphinoyl titanium(IV) adducts. All products were characterized by elemental analyses, spectroscopic and spectrometric methods and, in addition, complexes 7a and 7b by single‐crystal X‐ray structure analysis.
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".