发明名称 |
Verfahren zur Herstellung von 2,4,5-Trifluorbenzolsäure. |
摘要 |
2,4,5-Trifluorobenzoic acid is prepared by converting 4,5-difluoroanthranilic acid to the corresponding amine salt, converting the amine salt to the corresponding diazonium tetrafluoroborate and decomposing the tetrafluoroborate in a Schiemann reaction. In a preferred preparation, the 10 percent HCl is added to solid 4,5-difluoroanthranilic acid in sufficient amount to dissolve the solid at 70 DEG C, the amine salt is isolated, aqueous NaNO2 is added to the isolated amine salt at 0 DEG C, followed by addition of 40 to 50 percent aqueous HBF4 at 0 DEG C, followed by separation of the tetrafluoroborate by cooling and filtering and then drying, and the dried separated tetrafluoroborate is thermally degraded to 2,4,5-trifluorobenzoic acid by heating at 125 to 140 DEG C. |
申请公布号 |
DE69003559(T2) |
申请公布日期 |
1994.02.03 |
申请号 |
DE1990603559T |
申请日期 |
1990.02.21 |
申请人 |
OCCIDENTAL CHEMICAL CORP., NIAGARA FALLS, N.Y., US |
发明人 |
LIN, HENRY C., GRAND ISLAND, N.Y. 14072, US;NOWAK, DEANNE M., DEPEW, N.Y. 14043, US |
分类号 |
C07C51/363;C07C63/70;(IPC1-7):C07C63/70 |
主分类号 |
C07C51/363 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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