| CAS No. | 1428573-91-4 |
| Molecular Formula | C5H4ClF2N3O2 |
| Molecular Weight | 211.55 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Compared with other compounds in its class, the molecular weight of 211.55 g/mol gives 5-Chloro-1-(2,2-difluoroethyl)-4-nitro-1H-pyrazole distinctive chromatographic separation conditions and mass-spectrometry parameter settings.
5-Chloro-1-(2,2-difluoroethyl)-4-nitro-1H-pyrazole (CAS 1428573-91-4), molecular formula C5H4ClF2N3O2 and molecular weight 211.55 g/mol, is a CATO reference standard with documented purity and traceability.
Owing to an amide group, a carboxylic acid group, a hydroxyl group, an ether linkage, fluorine/chlorine substitution, 5-Chloro-1-(2,2-difluoroethyl)-4-nitro-1H-pyrazole is typically off-white to pale yellow crystalline powder. Its solid-state physicochemical attributes — including a molecular weight of 211.55 g/mol — guide the selection of appropriate sample preparation and analytical techniques. The presence of an aromatic ring or conjugated system gives the compound characteristic absorption bands in the UV-Vis region, making it well suited to UV or diode-array detection (DAD).
This reference standard is suitable for quantitative analysis on major chromatographic platforms including HPLC, GC, LC-MS/MS, and GC-MS, serving as an external calibration standard or a system suitability test reference material.
The assigned purity is verified by mass-balance and quantitative NMR (qNMR) approaches, with the expanded uncertainty reported at a 95% confidence level (k=2). Batch homogeneity and stability are independently assessed for every lot.
| Molecular Formula | C5H4ClF2N3O2 |
| Molecular Weight | 211.55 g/mol |
| Appearance | Off-white to pale yellow crystalline powder. (slight halide-like odor, faint amine-like odor, low volatility) |
| Purity | 97%+ |
| Storage | Store at 2-8°C, protect from light, keep sealed and dry, keep tightly closed to prevent evaporation |
| Solubility (reference) | Soluble in DMSO, DMF, methanol |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light; Hygroscopic; reseal immediately after opening; Contains ester bond; hydrolyzes under strong alkaline conditions |
| Degree of Unsaturation (DBE) | 4.0 |
| UV Absorption | UV-absorbing |
| CAS Registry Year (est.) | 1991 |
| Halogen Content | F/Cl-containing |
| Nitrogen Atoms | 3 |