Synthesis and characterization of a spirocyclic phosphaverdazyl radical - cyclophosphazene hybrid: Evidence for spin transfer from a verdazyl radical to a phosphazene ring
Bibliographic record
Abstract
The synthesis and characterization of a new 6-phosphaverdazyl radical incorporated into a spirocyclic framework containing a cyclotriphosphazene ring is described. Reaction of 1,1,3,3-bis[spiro-2',2''-dioxy-1',1''-biphenyl]-5,5-bis(1-methylhydrazido)-1,3,5,2,4,6-cyclotriphosphazene (7) with trimethylorthobenzoate yielded 6-[2,2,4,4-bis(2,2'-dioxy-1,1'-biphenyl)-2,4,6,1,3,5-cyclotriphosphazen-6-yl]-1,2,5,6-tetrahydro-1,5-dimethyl-3-phenyl-1,2,4,5,6-tetrazaphosphorine (8), which was characterized spectroscopically and by X-ray diffraction. Oxidation of 8 yielded 6-[2,2,4,4-bis(2,2'-dioxy-1,1'-biphenyl)-2,4,6,1,3,5-cyclotriphosphazen-6-yl]-1,5-dimethyl-3-phenyl-6-phosphaverdazyl (5), which was characterized by EPR and ENDOR spectroscopy. Analysis of both spectra indicate that spin density from the phosphaverdazyl ring induces spin polarization into the phosphazene ring, as evidenced by hyperfine coupling to all three phosphorus nuclei.Key words: heterocycle, phosphorusnitrogen compounds, phosphazenes, stable radicals, verdazyls.
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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".