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| | 2,4,6-Collidine Basic information |
| Product Name: | 2,4,6-Collidine | | Synonyms: | 2,4,6-Kollidin;2,4,6-trimethyl-pyridin;a,g,a'-Collidine;alpha,gamma,alpha’-collidine;alpha,gamma,alpha'-Collidine;g-Collidine;Pyridine,2,4,6-trimethyl-;2 Minus 2-3 Methyl pyridine | | CAS: | 108-75-8 | | MF: | C8H11N | | MW: | 121.18 | | EINECS: | 203-613-3 | | Product Categories: | Heterocyclic Compounds;bc0001;108-75-8 | | Mol File: | 108-75-8.mol |  |
| | 2,4,6-Collidine Chemical Properties |
| Melting point | -43 °C (lit.) | | Boiling point | 171-172 °C (lit.) | | density | 0.917 g/mL at 25 °C (lit.) | | vapor pressure | 4 hPa (20 °C) | | refractive index | n20/D 1.498(lit.) | | Fp | 135 °F | | storage temp. | Store below +30°C. | | solubility | 35g/l | | form | Liquid | | pka | 7.43(at 25℃) | | color | Clear colorless to yellow | | Water Solubility | 35 g/L (20 ºC) | | Sensitive | Hygroscopic | | Merck | 14,9718 | | BRN | 107283 | | Stability: | Stable. Combustible. Incompatible with strong oxidizing agents. | | LogP | 1.25 at 20℃ | | CAS DataBase Reference | 108-75-8(CAS DataBase Reference) | | NIST Chemistry Reference | Pyridine, 2,4,6-trimethyl-(108-75-8) | | EPA Substance Registry System | 2,4,6-Trimethylpyridine (108-75-8) |
| | 2,4,6-Collidine Usage And Synthesis |
| Chemical Properties | colourless liquid | | Uses | 2,4,6-Collidine is an reagent used for various synthetic preparations such as the synthesis of methylated pyridines by three-componet catalytic condensation of acetylene, acetone and ammonia. | | Uses | 2,4,6-Collidine is used as a tissue fixative for electron microscopy. It is useful in dehydrohalogenation reactions and acts as a solvent for the cleavage of hindered esters by anhydrous lithium iodide. | | Definition | Methyl, ethyl, propyl, and trimethyl homologs of
pyridine. | | Synthesis Reference(s) | Journal of the American Chemical Society, 72, p. 4184, 1950 DOI: 10.1021/ja01165a097 | | General Description | 2,4,6-Trimethylpyridine is a pyridine derivative. It has a pK of 7.4. The product can react with trifluoroiodomethane in cyclopentane solution to afford 1:1 complex. This complex was investigated by NMR (Nuclear Magnetic Resonance) spectroscopy. Collidine-buffered osmium tetroxide solutions have been prepared by adding osmium tetroxide solution to it. These solutions have been used as fixative for electron microscopic studies.
2,4,6-Trimethylpyridine can undergo oxidation with potassium permanganate to form 2,4,6-pyridinetricarboxylic acid. | | Hazard | Toxic. | | Flammability and Explosibility | Flammable | | Purification Methods | Commercial samples may be grossly impure. Likely contaminants include 3,5-dimethylpyridine, 2,3,6-trimethylpyridine and water. Brown, Johnson and Podall [J Am Chem Soc 76 5556 1954] fractionally distilled 2,4,6-trimethylpyridine under reduced pressure through a 40cm Vigreux column (p 11) and added to 430mL of the distillate slowly, with cooling to 0o, 45g of BF3-diethyl etherate. The mixture was again distilled, and an equal volume of dry *benzene was added to the distillate. Dry HCl was passed into the solution, which was kept cold in an ice-bath, and the hydrochloride was filtered off. It was recrystallised from absolute EtOH (1.5mL/g) to m 286-287o[m 256o(sealed tube), also m 293-294o subliming slowly]. The free base was regenerated by treatment with aqueous NaOH, then extracted with *benzene, dried (MgSO4) and distilled under reduced pressure. Sisler et al. [J Am Chem Soc 75 446 1953] precipitated trimethylpyridine as its phosphate from a solution of the base in MeOH by adding 85% H3PO4, shaking and cooling. The free base was regenerated as above. Garrett and Smythe [J Chem Soc 763 1903] purified the trimethylpyridine via the HgCl2 complex. It is more soluble in cold than hot H2O [the solubility is 20.8% at 6o, 3.5% at 20o, 1.8% at 100o]. Alternatively, purify it by dissolving it in CHCl3, adding solid K2CO3 and Drierite, filtering and fractionally distilling through an 8in helix-packed column. The sulfate has m 205o, and the picrate (from hot H2O) has m 155-156o. [Frank & Meikle J Am Chem Soc 72 4184 1950, Beilstein 20 H 250, 20 I 87, 20 II 164, 20 III/IV 2810, 20/6 V 93.] |
| | 2,4,6-Collidine Preparation Products And Raw materials |
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