5‐Chloro‐ <i>N</i> ‐(di‐ <i>tert</i> ‐butylphosphaneyl)‐ <i>N</i> ‐methylpyrazin‐2‐amine
Bibliographic record
Abstract
image [2981401‐76‐5] C 13 H 23 ClN 3 P (MW 287.77) InChI = 1S/C13H23ClN3P/c1‐12(2,3)18(13(4,5)6)17(7)11‐9‐15‐10(14)8‐16‐11/h8‐9H,1‐7H3 InChIKey = WNSRMVGRQQVGJQ‐UHFFFAOYSA‐N (ligand for gold‐catalyzed cross‐coupling reactions 1 ) Alternative Name(s): ClKarPhos. Solubility: soluble in CHCl 3 , DCM, DCE, Et 2 O, THF. Form Supplied in: light orange solid. Analysis of Reagent Purity: 1 H NMR (300 MHz, CDCl3) δ (ppm) 8.89 (dd, J = 4.5, 1.5 Hz, 1 H ), 8.05 (dd, J = 1.5, 0.7 Hz, 1 H ), 3.24 (s, 3 H ), 1.25 (d, J = 12.8 Hz, 18 H ). 13 C NMR (75 MHz, CDCl3) δ (ppm) 158.1 (d, J = 24.7 Hz), 139.9, 136.8 (d, J = 2.7 Hz), 134.6 (d, J = 36.9 Hz), 37.2 (d, J = 7.4 Hz), 36.2 (d, J = 27.8 Hz), 29.8 (d, J = 16.7 Hz). 31 P NMR (122 MHz, CDCl3) δ (ppm) 85.0 HRMS (ESI) Calculated for C 13 H 24 ClN 3 P + [M+H] + : 288.1391; found: m/z 288.1378. Preparative Methods 1 : a flame‐dried Schlenk flask was charged with the 5‐chloro‐ N ‐methylpyrazin‐2‐amine (65 mg, 0.45 mmol) and dry THF [0.2 M] under a nitrogen atmosphere. The resulting solution was cooled down to 0 °C before a solution of n ‐BuLi in hexane (0.18 mL, 0.45 mmol) was added dropwise. The reaction mixture was allowed to reach room temperature and was then stirred for 4 hours before t Bu 2 PCl (86 μL, 91 mg, 0.45 mmol) was added dropwise. At the end of the addition, the temperature was raised to 60 °C and the reaction mixture was stirred for 3 days (eq ). The solvent was then evaporated, and the crude residue was purified by flash column chromatography using a 10:1 hexanes:ethyl acetate mixture as the eluent. image Purification: purification by flash column chromatography in hexanes:ethyl acetate = 10:1. Handling, Storage, and Precautions: bench stable, long‐term storage under nitrogen atmosphere and refrigerate to prevent degradation.
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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 | 0.000 | 0.003 |
| Meta-epidemiology (narrow) | 0.002 | 0.002 |
| Meta-epidemiology (broad) | 0.003 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.003 | 0.001 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.062 | 0.001 |
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; both teacher heads agree on what is shown here.
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".