公开(公告)号：US5352840A

公开(公告)日：1994-10-04

申请号：US59157

申请日：1993-05-10

申请人： Stephen G. Grundy ,  Kevan M. Reeve ,  Michael C. Rocca

发明人： Stephen G. Grundy ,  Kevan M. Reeve ,  Michael C. Rocca

IPC分类号： C07C45/28 ,  C07C45/27 ,  C07C45/30

CPC分类号： C07C45/28

摘要： Substituting aqueous hydrogen peroxide/hydrogen bromide for bromine in a known process for producing a ditertiaryalkyl substituted hydroxybenzaldehyde such as ditertiarybutyl hydroxybenzaldehyde from the corresponding ditertiaryalkyl substituted methylphenol results in a substantially impaired yield of product.Improved yields are obtained by employing a reaction temperature of at least 40.degree. C., preferably 50.degree. to 80.degree. C. in conjunction with a hydrophobic solvent such as chloroform. Preferably, the process employs very concentrated hydrogen peroxide solution, 65% to 75% w/w, introduced into the bromide-containing reaction mixture during a period of from 25 to 75 minutes.

摘要翻译： 在已知的二氯烷基取代的羟基苯甲醛的制备方法中代替溴化氢水溶液，例如从相应的二叔丁基取代的甲基苯酚得到的二叔丁基羟基苯甲醛导致产物的产率显着降低。 通过使用至少40℃，优选50-80℃的反应温度与疏水性溶剂如氯仿来获得提高的产率。 优选地，该方法在25至75分钟的时间内将非常浓缩的过氧化氢溶液（65％至75％w / w）引入含溴化物的反应混合物中。

公开(公告)号：US4923580A

公开(公告)日：1990-05-08

申请号：US326065

申请日：1989-03-20

申请人： Philip J. Turner ,  Martin Jeff ,  Kevan M. Reeve

发明人： Philip J. Turner ,  Martin Jeff ,  Kevan M. Reeve

IPC分类号： B01J19/12 ,  C07B39/00 ,  C07C17/00 ,  C07C17/14 ,  C07C22/04 ,  C07C25/02 ,  C07C25/13 ,  C07C45/43 ,  C07C67/00 ,  C07C201/00 ,  C07C201/12 ,  C07C201/14 ,  C07C205/11 ,  C07C205/12 ,  C07C303/22 ,  C07C309/30

CPC分类号： C07B39/00 ,  C07C201/12

摘要： Selective bromination of alkylarenes to the alpha dibrominated derivative is desirable as a precursor for the selective production of, for example, the corresponding aromatic aldehyde.Improvements in the extent of selectivity of the product and/or its rate of production can be obtained by employing a photolytic reaction between the substrate, hydrogen peroxide and hydrogen bromide using mole ratios of H.sub.2 O.sub.2 : substrate of about 2.8:1 or higher, preferably 3,2: to 3.5:1 and of bromide:substrate of over 2.5:1, preferably about 2.8:1 to 3.2:1 and progressive controlled introduction of the H.sub.2 O.sub.2, the reaction being carried out in the presence of a substantial amount of an organic solvent, and preferably more than 5.5 volumes per volume of substrate, whilst irradiating with light preferably having principal emissions in the range of 250 to 600 nm. The reaction mixture is preferably maintained at 50.degree. to 60.degree. C. The reaction often takes from 5 to 12 hours, of which period hydrogen peroxide is introduced progressively into the reaction mixture during preferably the first 3 to 5 hours. The process is especially suitable for deactivated alkylarenes, such as o-nitrotoluene.

公开(公告)号：US5139628A

公开(公告)日：1992-08-18

申请号：US674380

申请日：1991-04-11

申请人： Kenneth M. Dear ,  Kevan M. Reeve ,  Philip J. Turner

发明人： Kenneth M. Dear ,  Kevan M. Reeve ,  Philip J. Turner

IPC分类号： C07C51/265 ,  C07C309/58 ,  C07F9/6547

CPC分类号： C07C309/58

摘要： A multi stage process for the conversion of 2-chloro-4-sulphotoluene (SCT) to 2-chloro-4-sulphobenzoic acid (SCUBA). Stage (a) comprises a process S1 for the selective side chain bromination of SCT to 2-chloro-4-sulpho-dibromotoluene (SCDBT) or 2-chloro-4-sulpho-bromotoluene (SCMBT) by contacting the starting material with bromine in chloroform or trichloroethane and irradiating the mixture with light that dissociates bromine. Subsequently, in stage (b), process S2, the product of S1 can be hydrolysed at elevated temperature after separation from the organic solvent to the corresponding alcohol (SCOL) or aldehyde (SCAB). In stage (c), the product of S2 can be oxidized to SCUBA either by oxidation with a peroxyacid, optionally generated in situ, provided that the aqueous solution has previously been stripped of bromide/bromine in process S3. The oxidation can also be carried out using bromine, preferably generated in situ in process S5 by oxidation of residual bromide with hydrogen peroxide, which can then be followed by process S3 to strip out the bromine/bromide. A combination of processes S1, S2, S5 and S3 in that order provides a closed loop process cycle which recycles the environmentally harmful reagent, bromine.

摘要翻译： PCT No.PCT / GB89 / 01068 Sec。 371日期1991年4月11日 102（e）日期1991年4月11日PCT提交1989年9月12日PCT公布。 出版物WO90 / 02731 1990年3月22日。用于将2-氯-4-磺基丙烯（SCT）转化为2-氯-4-磺基苯甲酸（SCUBA）的多阶段方法。 阶段（a）包括通过使原料与溴接触，将SCT的选择性侧链溴化为2-氯-4-磺基 - 二溴甲苯（SCDBT）或2-氯-4-磺基 - 溴甲苯（SCMBT）的方法S1 氯仿或三氯乙烷，并用分解溴的光照射混合物。 随后，在步骤（b）中，方法S2中，S1的产物可以在从有机溶剂分离到相应的醇（SCOL）或醛（SCAB）之后在升高的温度下水解。 在阶段（c）中，S2的产物可以通过过氧酸的氧化被氧化成SCUBA，任选地原位生成，条件是在方法S3中先前已经将水溶液除去了溴化物/溴。 氧化还可以使用溴进行，优选在方法S5中原位通过用过氧化氢氧化残余溴化物，然后可以通过方法S3除去溴/溴。 过程S1，S2，S5和S3的组合按照该顺序提供闭环处理循环，其循环利用环境有害的试剂溴。