Crystal structure of 4′-bromo-2,5-dihydroxy-2′,5′-dimethoxy-[1,1′-biphenyl]-3,4-dicarbonitrile
Bibliographic record
Abstract
In the crystal of the title substituted hemibi-quinone derivative, C16H11BrN2O4 or [BrHBQH2(CN)2], the substituted benzene rings are rotated about the central C-C bond, forming a dihedral angle of 53.59 (7)°. The ring systems inter-act through an intra-molecular O-H⋯Ometh-oxy hydrogen bond, which induces a geometry quite different from those in previously reported hemibi-quinone structures. In the crystal, the mol-ecules associate through an inter-molecular O-H⋯Nnitrile hydrogen bond, forming chains which extend along [100] and are inter-linked through very weak C-H⋯N hydrogen bonds, giving a overall two-dimensional structure lying parallel to (010).
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.003 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| 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 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".