Carbonylation of Dinitrotoluene to Dimethyl Toluenedicarbamate; High Efficiency of Phosphorus Acids as Promoters for the Palladium-Phenanthroline Catalytic System
Phosphorusacids are excellent promoters for the palladium-phenanthroline catalyzed carbonylation of 2,4-dinitrotoluene to 2,4-toluenedicarbamate. For the first time, all intermediate nitrocarbamates and aminocarbamates have been independently synthesized and their amount after every catalytic reaction precisely quantified. An extensive optimization of all experimental variables has been carried out
磷酸是钯-菲咯啉催化的2,4-二硝基甲苯羰基化为2,4-甲苯二氨基甲酸酯的极好促进剂。第一次,所有中间体硝基氨基甲酸酯和氨基甲酸酯都被独立合成,并且在每次催化反应后它们的数量都被精确地定量了。已经对所有实验变量进行了广泛的优化。最好的酸是苯基膦酸和4-甲苯基膦酸。添加2,2-二甲氧基丙烷作为内部干燥剂是非常有益的。衍生自起始二硝基芳烃的胺的加入提高了羰基化反应的速率和选择性。配合物[Pd(Phen)2 ] [SbF 6 ]和[Pd(Phen)2 ] [BAr F 4首次制备了[Ar F= 3,5-(CF 3)2 C 6 H 3 ]。后者显示出比所有其他[Pd(Phen)2 ] 2+复合物明显更高的溶解度。还研究了几种可能的启动子的作用。在优化的实验条件下,当以二硝基甲苯/ Pd = 2920的摩尔比工作时,在二氨基甲酸酯中的选择性为77.6%。在反应结束时,冷却后,二氨基甲酸酯自发从溶液中
[EN] ZINC CLUSTER COMPOUNDS AND THEIR USE AS CATALYSTS IN THE REACTION OF AMINES WITH DIALKYL CARBONATES<br/>[FR] COMPOSÉS AGRÉGATS DE ZINC ET LEUR UTILISATION COMME CATALYSEURS DANS LA RÉACTION ENTRE AMINES ET CARBONATES DE DIALKYLE
申请人:BAYER MATERIALSCIENCE AG
公开号:WO2014187756A1
公开(公告)日:2014-11-27
The present invention relates to metallic zinc cluster compounds which are suitable as catalysts in the reaction of amines with dialkyl carbonates to produce carbamates. The invention is also directed towards a method for the alkoxycarbonylation of amines. The cluster compound has a general formula which may be written as [M(O2C-R)2]x- [MO]y- [H2O]z, wherein M is Zn, R is an unsubstituted or substituted aromatic, cycloaliphatic, linear aliphatic, or other organic rest, x is 1, y is > x is 1, y is > 0.03 to < 26.0 and z is > 0.00 to < 17.0.
METHOD FOR TREATMENT OF ISOCYANATE RESIDUE, AND METHOD FOR TREATMENT OF CARBONATE
申请人:Shimokawatoko Yoshiki
公开号:US20120271067A1
公开(公告)日:2012-10-25
A method for treating an isocyanate residue, which comprises carrying out a thermal decomposition reaction of a carbamate that is produced by the reaction among an amine, urea and/or an N-unsubstituted carbamic acid ester and an alcohol to produce a decomposition solution, separating an isocyanate and the alcohol from the decomposition solution to produce the isocyanate residue, and bringing the isocyanate residue into contact with high-pressure/high-temperature water to decompose the isocyanate residue into an amine; and a method for treating a carbonate, which comprises bringing the carbonate into contact with high-pressure/high-temperature water to decompose the carbonate into an alcohol.
Verfahren zur thermischen Spaltung Carbamidsäureestern
申请人:BAYER AG
公开号:EP0795544A1
公开(公告)日:1997-09-17
Die Erfindung betrifft ein Verfahren zur thermischen Spaltung von Carbamidsäureestern in die korrespondierenden Isocyanate und die Hydroxylkomponenten in der Flüssigphase, wobei die Reaktion im Abtriebsteil einer Kolonne als Reaktivrektifikation abläuft und ein inertes schwersiedendes Lösemittel als Puffer die Reaktion aus dem Verdampferbereich der Kolonne fernhält.
Verwendung von hochsiedenden Lösemitteln bzw. -gemischen als Wärmetauschmedium für die thermische Spaltung von Carbamidsäureestern
申请人:BAYER AG
公开号:EP0795543A1
公开(公告)日:1997-09-17
Die Erfindung betrifft die Verwendung von definiert bzw. in einem engen Bereich siedenden inerten thermostabilen Lösemitteln bzw. -gemischen als Wärmetauschmedium für die thermische Spaltung von Carbamidsäureestern (Urethanspaltung).