pyrrole
pyr·role
P0691400 (pîr′ōl′)pyrrole
(ˈpɪrəʊl; pɪˈrəʊl)pyr•role
(pɪˈroʊl, ˈpɪr oʊl)n.
单词 | pyrrole |
释义 | pyrrolepyr·roleP0691400 (pîr′ōl′)pyrrole(ˈpɪrəʊl; pɪˈrəʊl)pyr•role(pɪˈroʊl, ˈpɪr oʊl)n. Pyrrolepyrrole[′pi‚rōl]Pyrrolea heterocyclic compound; colorless liquid that darkens rapidly upon exposure to air. Melting point, — 23.42°C; boiling point, 130°C; density, 0.9698 g/cm3 at 20°C. Moderately soluble in water. Pyrrole is a very weak acid; it forms a salt with potassium or anhydrous caustic potash. It resinifies under the influence of acids, and it oxidizes readily. It hydrogenates with H2 over Ni at 200°C to pyrrolidine. Pyrrole was first isolated from coal tar. It is produced commercially by dry distillation of the ammonia salt of mucic acid or by passing a mixture of furan and NH3 over Al2O3 at 400°–450°C. The pyrrole nucleus is a structural fragment of porphyrin molecules. Pyrrole is used in the production of pyrrolidine and in the synthesis of pharmaceuticals—for example, the antiseptic Iodol (2,3,4,5-tetraiodopyrrole). pyrrolepyrrole[pir´ōl]pyr·role(pir'ōl),pyrrole(pîr′ōl′)pyr·role(pir'ōl)Synonym(s): azole, imidole. pyrrolea porphyrin building block that has a five-membered heterocyclic structure and contains nitrogen. |
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