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/Schiff Base/Pd Complex as an Efficient Heterogeneous and Recyclable Nanocatalyst for One-Pot Domino Synthesis of Carbamates and Unsymmetrical Ureas
作者:Iman Dindarloo Inaloo、Sahar Majnooni
DOI:10.1002/ejoc.201901140
日期:2019.10.9
A palladium‐catalyzed domino method for the direct synthesis of carbamates and ureas has been developed by using readily available and economical starting materials (arylhalide, carbon monoxide, sodium azide, amines, and alcohols) in a one‐pot approach. This efficient and phosgene‐free process provided an inexpensive and attractive route to synthesize the products in good to excellent yields.
The invention relates to a method for producing an isocyanate, wherein a carbamate or thiolcarbomate is converted, in the presence of a catalyst, with separation of an alcohol or thioalcohol, at a temperature of at least 150° C., to the corresponding isocyanate, wherein a compound of the general formula (X)(Y)(Z—H) is used as a catalyst, in particular characterized in that the compound has both a proton donor function and a proton acceptor function. In the catalysts according to the invention, a separable proton is bound to a heteroatom, which is more electronegative than carbon. Said heteroatom is either identical to Z or a component thereof. In the catalysts according to the invention, there is additionally a proton acceptor function which is either identical to X or a component thereof. According to the invention, the proton donator and proton acceptor function are connected to each other by the bridge Y.
Zinc incorporated covalent organic framework (Zn@DBPG): an efficient catalyst for the synthesis of carbamates through CO2 and non CO2 fixation pathways under sustainable condition
作者:Najirul Haque、Surajit Biswas、Malay Dolai、Dip Kumar Nandi、Mainak Sarkar、Sk Manirul Islam
DOI:10.1016/j.mcat.2022.112900
日期:2023.2
organic framework constructed zinc catalyst; Zn@DBPG is synthesized and characterized properly. The synthesized material is utilized as an efficient catalyst for the production of organic carbamates following two different pathways: one is carbondioxide fixation path and another is non carbondioxide track undermildreactionconditions. In CO2 fixation track, both alkyl halides and aryl halides produced
The invention relates to a method for producing an isocyanate, wherein a carbamate or thiolcarbomate is converted, in the presence of a catalyst, with separation of an alcohol or thioalcohol, at a temperature of at least 150° C., to the corresponding isocyanate, wherein a compound of the general formula (X)(Y)(Z—H) is used as a catalyst, in particular characterized in that the compound has both a proton donor function and a proton acceptor function. In the catalysts according to the invention, a separable proton is bound to a heteroatom, which is more electronegative than carbon. Said heteroatom is either identical to Z or a component thereof. In the catalysts according to the invention, there is additionally a proton acceptor function which is either identical to X or a component thereof. According to the invention, the proton donator and proton acceptor function are connected to each other by the bridge Y.
本发明涉及一种生产异氰酸酯的方法,其中氨基甲酸酯或硫代氨基甲酸酯在催化剂存在下,与醇或硫代醇分离,在至少150℃的温度下转化为相应的异氰酸酯,其中通式(X)(Y)(Z-H)的化合物用作催化剂,特别是该化合物具有质子供体功能和质子受体功能。在本发明的催化剂中,可分离质子与一个杂原子结合,该杂原子的电负性比碳强。所述杂原子要么与 Z 相同,要么是其组成部分。在本发明的催化剂中,还有一个质子受体官能团,它或者与 X 相同,或者是其中的一个组分。根据本发明,质子供体和质子受体功能通过桥 Y 相互连接。
Yew, Kyoung Han; Koh, Han Joong; Lee, Hai Whang, Journal of the Chemical Society. Perkin transactions II, 1995, # 12, p. 2263 - 2268
作者:Yew, Kyoung Han、Koh, Han Joong、Lee, Hai Whang、Lee, Ikchoon