carbonate and much less reactive methyl carbamates with primary (1°), secondary (2°), and tertiary (3°) alcohols was established with the use of a lanthanum(III) complex, which was prepared in situ from lanthanum(III) isopropoxide (3 mol %) and 2-(2-methoxyethoxy)ethanol (6 mol %). In particular, corresponding carbonates and carbamates obtained were of synthetic utility from the viewpoint of the selective protection
Facile one-pot synthesis of unsymmetrical ureas, carbamates, and thiocarbamates from Cbz-protected amines
作者:Hee-Kwon Kim、Anna Lee
DOI:10.1039/c6ob01290f
日期:——
A novel one-potsynthesis of unsymmetricalureas, carbamates and thiocarbamates from Cbz-protected amines has been developed. In the presence of 2-chloropyridine and trifluoromethanesulfonyl anhydride, isocyanates are generated in situ, which facilitate rapid reaction with amines, alcohols, and thiols to afford the corresponding ureas, carbamates and thiocarbamates in high yields.
Dehydrogenative Synthesis of Carbamates from Formamides and Alcohols Using a Pincer-Supported Iron Catalyst
作者:Tanya M. Townsend、Wesley H. Bernskoetter、Nilay Hazari、Brandon Q. Mercado
DOI:10.1021/acscatal.1c02718
日期:2021.8.20
already been demonstrated that the transient isocyanate generated from dehydrogenation of the formamide can be trapped with amines to form ureas and, in principle, the isocyanate could also be trapped with thiols to form thiocarbamates. Competition experiments indicate that trapping of the transient isocyanate with amines to produce ureas is faster than trapping with an alcohol to produce carbamates
Method for the synthesis of N-alkyl-O-alkyl carbamates
作者:Victoria A. Vaillard、Marianela González、Jesica P. Perotti、Ricardo J. A. Grau、Santiago E. Vaillard
DOI:10.1039/c4ra00373j
日期:——
Simple three step method for the synthesis of N-alkyl, O-alkyl carbamates.
合成N-烷基,O-烷基氨基甲酸酯的简单三步方法。
Metal Identity Effects in the Pincer Complex-Catalyzed Dehydrogenative Coupling of Formamides with Alcohols to Form Carbamates
作者:Abebu A. Kassie、Ila Y. Castro De la Torre、Matthew S. Remy、Sukrit Mukhopadhyay、Jeff Kampf、Fengrui Qu、Melanie S. Sanford
DOI:10.1021/acs.organomet.3c00175
日期:2023.5.22
along with the corresponding carbamate. In contrast, all three of the N-bound metallacycles show dramatically lower reactivitytoward catalyst regeneration under analogous conditions. The reactivity of the pincer complexes toward formamide dehydrogenation also varies as a function of metal, with Ru and Fe ≫ Mn at 100 °C. Overall, the Mn pincer complex is an effective catalyst for the conversion of a variety
这份手稿描述了金属(钌与铁与锰)对甲酰胺与醇的 PNP 钳络合物催化脱氢偶联产生氨基甲酸酯的影响。进行研究以比较关键有机金属中间体的结构和反应性作为金属的功能。这些表明所有三种钳形催化剂都与异氰酸酯(甲酰胺脱氢的初始有机产物)快速反应,形成非循环金属环物质。然而,这些中间体的结构和反应性随金属的变化而变化。金属环的 N 键异构体由 Fe(文献)和 Ru(这项工作)形成,而 O 键(动力学)和 N 键(热力学)金属环均与 Mn 一起观察(这项工作)。在 100°C 时,与 O 结合的 Mn 环加合物与环己醇快速反应,释放钳形催化剂以及相应的氨基甲酸酯。相比之下,所有三种 N 结合的金属环在类似条件下都显示出对催化剂再生显着降低的反应性。钳状配合物对甲酰胺脱氢的反应性也随金属的变化而变化,在 100 °C 时,Ru 和 Fe ⇒ Mn。总的来说,锰螯合物是一种有效的催化剂,可在 150 °C