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    High purity 2,4-dinitrotoluene from toluene nitration process
    222.
    发明授权
    High purity 2,4-dinitrotoluene from toluene nitration process 失效
    甲苯硝化过程中的高纯度2,4-二硝基甲苯

    公开(公告)号：US4367347A

    公开(公告)日：1983-01-04

    申请号：US269137

    申请日：1981-06-01

    Applicant: John E. Sawicki

    Inventor： John E. Sawicki

    IPC: C07C67/00 ,  C07C201/00 ,  C07C201/16 ,  C07C205/06 ,  C07C79/10

    CPC classification number: C07C201/16

    Abstract: A method for preparing substantially pure 2,4-DNT isomer from its admixture with other DNT isomers which comprises contacting the isomer mixture with aqueous sulfuric acid at an elevated temperature, separating excess DNT isomer mixture from the sulfuric acid phase and cooling the sulfuric acid phase. Also, in a method for producing dinitrotoluenes which comprises:(a) nitrating toluene in a first nitration stage with an aqueous mixture of sulfuric and nitric acids to form an organic phase containing mononitrotoluenes and a first aqueous spent acid phase;(b) separating the organic phase from the first aqueous spent acid phase;(c) nitrating the mononitrotoluenes contained in the organic phase in a second nitration stage using a mixture of sulfuric and nitric acids to form an organic phase containing dinitrotoluenes and a second aqueous spent acid phase; and(d) separating the organic phase from the second aqueous spent acid phase for recovery of the dinitrotoluene product from the organic phase;the novel feature comprising:(e) cooling at least a portion of the first or second aqueous spent acid phase to a temperature sufficient to effect crystallization of substantially pure 2,4-DNT;(f) recovering the 2,4-DNT crystals from the cooled aqueous spent acid phase; and(g) returning the portion of the cooled spent acid phase to a nitration stage.

    Abstract translation: 从其与其它DNT异构体的混合物制备基本上纯的2,4-DNT异构体的方法，其包括在高温下使异构体混合物与硫酸水溶液接触，从硫酸相分离过量的DNT异构体混合物并冷却硫酸相 。 此外，在制备二硝基甲苯的方法中，其包括：（a）在第一硝化阶段用硫酸和硝酸的含水混合物硝化甲苯以形成含有单硝基甲苯和第一含水废酸相的有机相; （b）将有机相与第一含水废酸相分离; （c）在第二硝化阶段使用硫酸和硝酸的混合物硝化有机相中所含的单硝基甲苯以形成含有二硝基甲苯和第二废酸水相的有机相; 和（d）将有机相与第二废酸水相分离，以从有机相中回收二硝基甲苯产物; 该新颖特征包括：（e）将至少一部分第一或第二含水废酸相冷却到足以实现基本上纯的2,4-DNT的结晶的温度; （f）从冷却的废酸水相中回收2,4-DNT晶体; 和（g）将冷却的废酸相的一部分返回到硝化阶段。

    Processes for the preparation of hydratropic acids and esters
    228.
    发明授权
    Processes for the preparation of hydratropic acids and esters 失效
    制备水合酸和酯的方法

    公开(公告)号：US4266069A

    公开(公告)日：1981-05-05

    申请号：US105063

    申请日：1979-12-19

    Applicant: Jerry A. Walker

    Inventor： Jerry A. Walker

    IPC: C07C69/003 ,  C07C51/00 ,  C07C51/38 ,  C07C57/38 ,  C07C57/46 ,  C07C57/52 ,  C07C57/58 ,  C07C59/42 ,  C07C67/00 ,  C07C67/32 ,  C07C67/343 ,  C07C69/65 ,  C07C69/76 ,  C07C201/00 ,  C07C205/56 ,  C07C253/00 ,  C07C255/57 ,  C07C79/46

    CPC classification number: C07C227/04 ,  C07C201/12

    Abstract: The invention concerns the novel compounds dialkyl 2-(3-fluoro-4-nitrophenyl)-2-methylmalonate IIIa and dialkyl 2-(3-fluoro-4-aminophenyl)-2-methylmalonate IVa useful as intermediates in an improved process for making 2-(2-fluoro-4-biphenylyl)propionic acid, known as flurbiprofen, having the formula ##STR1## and ester thereof. It has anti-inflammatory activity which is about 240 times that of aspirin and analgesic activity which is about 180 times that of aspirin in standard laboratory tests. However, despite this high activity, the toxicity (LD.sub.50) is only 1.2 to 2.4 times greater than that of aspirin in standard laboratory tests.Also within the invention is a novel method of making the above intermediates and analogs thereof useful to prepare corresponding biaryl compounds which have pharmaceutical uses.

    Abstract translation: 本发明涉及新型化合物2-（3-氟-4-硝基苯基）-2-甲基丙二酸二烷基酯IIIa和2-（3-氟-4-氨基苯基）-2-甲基丙二酸二烷基酯IVa，其用作改进的制备方法中的中间体 称为氟比洛芬的2-（2-氟-4-联苯基）丙酸，其具有式Ia及其酯。 它具有约240倍的阿斯匹林和止痛活性的抗炎活性，约为阿司匹林在标准实验室检测中的约180倍。 然而，尽管活性高，但在标准实验室检测中，毒性（LD50）仅为阿司匹林的1.2〜2.4倍。 本发明还有一种使上述中间体及其类似物用于制备具有药物用途的相应联芳基化合物的新方法。

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