A Hydrazine- and Phosgene-Free Synthesis of Tetrazinanones, Precursors to 1,5-Dialkyl-6-Oxoverdazyl Radicals
Bibliographic record
Abstract
A complementary approach to published synthetic methods for tetrazinanones, precursors to verdazyl radicals, is described herein. This approach uses carbohydrazide, a commercially available reagent, as a common starting material. Unlike previous methods described in the literature, this synthetic scheme does not rely on phosgene, phosgene substitutes, or the limited pool of commercially available monosubstituted hydrazines for its execution. A large variety of alkyl substitution patterns at the N-1 and N-5 positions of verdazyl radicals are possible, including both symmetrically and unsymmetrically substituted products. An initial condensation reaction of carbohydrazide with a specific aldehyde introduces the desired C-3 substituent in the final verdazyl radical product and protects the NH(2) groups during the subsequent N-1 and N-5 alkylation reactions. A succeeding methanolysis and concomitant ring-closing reaction gives the tetrazinanone. A number of known oxidation methods can then be employed to form the final verdazyl radical product.
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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) | 0.000 | 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 | 0.001 | 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".