Unlocking CO<sub>2</sub> Activation With a Novel Ni−Hg−Ni Trinuclear Complex
Bibliographic record
Abstract
Abstract Compounds featuring bonds between mercury and transition metals are of interest for their intriguing/ambiguous bonding and scarcely explored reactivities. We report herein the synthesis and reactivities of the new compound [(POCOP)Ni] 2 Hg, [Ni 2 Hg] , featuring a trinuclear Ni−Hg−Ni core (POCOP= κ P , κ C , κ P' ‐2,6‐( i ‐Pr 2 PO) 2 C 6 H 3 ). [Ni 2 Hg] reacts with CO 2 to give the carbonate‐bridged complex [Ni 2 CO 3 ] . Bubbling CO gas through a solution of [Ni 2 CO 3 ] gave its μ ‐CO 2 analogue [Ni 2 CO 2 ] , which itself reacts with CO 2 to give back [Ni 2 CO 3 ] , indicating that these two compounds interconvert reversibly. This implies that the formation of [Ni 2 CO 3 ] from [Ni 2 Hg] and CO 2 constitutes a reductive disproportionation of two molecules of CO 2 into CO 3 2− and CO. Tests showed that this process proceeds through three steps, an initial CO 2 insertion to give [Ni 2 CO 2 ] , followed by another CO 2 insertion to give the second intermediate [Ni 2 C 2 O 4 ] , and the latter's decarbonylation to give [Ni 2 CO 3 ] . Although the putative second intermediate could not be isolated, we have shown that it likely features a μ ‐carbonyl‐carbonate rather than a μ ‐oxalate moiety, because the latter complex is thermally stable to decarbonylation. Reduction of [Ni 2 CO 3 ] with excess Na/Hg regenerates [Ni 2 Hg] , establishing that the observed deoxygenation of CO 2 in this system can, in principle, be catalytic in the presence of excess reductant.
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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| 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) | 0.000 | 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".