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ChemicalBook CAS DataBase List Pyrene
129-00-0

Pyrene synthesis

11synthesis methods
The content in high temperature tar is about 1.2% ~ 1.8%, which is prepared by separation and purification. Using anthracene oil as raw material, vacuum distillation, extraction, recrystallization and purification. The residue of distilled anthracene oil above 360 ℃ is used as raw material, the pyrene fraction is cut by distillation, benzene is used as solvent, washed with concentrated sulfuric acid, the base and unsaturated compounds are removed, and then the pure product is recrystallized with solvent oil. It can also be extracted from tobacco. Pyrene mainly exists in the distillate of coal tar pitch. The medium temperature asphalt is distilled under reduced pressure, and a small amount of direct superheated steam is introduced into the distillation kettle to cut the narrow fraction of pyrene, and then recrystallized with the mixed solution of solvent oil and ethanol or the mixed solution of benzene and solvent oil to obtain industrial pyrene with a purity of 95%.
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Yield:-

Steps:

Multi-step reaction with 2 steps
1.1: n-butyllithium / tetrahydrofuran / 3 h / -78 °C
1.2: -78 - 20 °C
1.3: 1 h
2.1: caesium carbonate / 1-methyl-pyrrolidin-2-one; water / 10 h / 100 °C

References:

Zhang, Xin;Zhao, Haitao;Wang, Jianhui [Journal of Nanoscience and Nanotechnology,2010,vol. 10,# 8,p. 5153 - 5160]

Pyrene Related Search:

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