Expeditious Synthesis of 2-Aryl Substituted Imidazolines and Imidazoles
摘要:
A versatile and efficient method for the synthesis of 2-aryl substituted imidazolines and imidazoles bearing a carboxylate group on C-4 is reported. Three different synthetic pathways were explored, compared and optimized. The selected procedure involves condensation of methyl 2,3-diaminopropionate with different imino ethers. The ring closure, monitored by LC-MS analysis, was facilitated by heating at reflux in ethanol leading to increase the rate of cyclization.
Aerobic Oxidative Amidation of Aromatic and Cinnamic Aldehydes with Secondary Amines by CuI/2-Pyridonate Catalytic System
作者:Mingwen Zhu、Ken-ichi Fujita、Ryohei Yamaguchi
DOI:10.1021/jo301553v
日期:2012.10.19
A simple and convenient CuI/2-pyridonate catalytic system for the oxidative amidation of aldehydes with secondary amines has been developed. With this system, a variety of useful arylamides have been synthesized in moderate to good yields in the presence of small amount of copper catalyst and the pyridonate ligand, generating only water as a coproduct. Synthesis of cinnamamides was also achieved by
An Acid-Stable <i>tert</i>-Butyldiarylsilyl (TBDAS) Linker for Solid-Phase Organic Synthesis
作者:Christine M. DiBlasi、Daniel E. Macks、Derek S. Tan
DOI:10.1021/ol050370y
日期:2005.4.1
robust tert-butyldiarylsilyl (TBDAS) linker has been developed for solid-phaseorganicsynthesis. This linker is stable to both protic and Lewis acidic reaction conditions, overcoming a significant limitation of previously reported silyl linkers. Solid-phase acetal deprotection, olefination, asymmetric allylation, and silyl protectinggroup deblocking reactions have been demonstrated with TBDAS-linked substrates
Free carboxylic acids are converted into amides in moderate to high yields in the presence of a stoichiometric amount of trimethylaluminium and amines at 90 ËC after 1 hour.
自由羧酸在三甲基铝和胺的存在下,以适中至高产率,在90摄氏度下经过1小时后转化为酰胺。
Cobalt-catalyzed aminocarbonylation of (hetero)aryl halides promoted by visible light
作者:Alexander M. Veatch、Erik J. Alexanian
DOI:10.1039/d0sc02178d
日期:——
aminocarbonylation of (hetero)arylhalides is widely applied in the synthesis of amides but relies heavily on the use of precious metal catalysis. Herein, we report an aminocarbonylation of (hetero)arylhalides using a simple cobalt catalyst under visible light irradiation. The reaction extends to the use of (hetero)aryl chlorides and is successful with a broad range of amine nucleophiles. Mechanistic investigations
Palladium-Catalyzed Aminocarbonylation of<i>N</i>-Chloroamines with Boronic Acids
作者:Wanfang Li、Xiao-Feng Wu
DOI:10.1002/chem.201500779
日期:2015.5.11
synthetic points of view, the carbonylative transformation of NX bonds represents an interesting and attractive area of investigation. In light of this, the first carbonylative cross‐coupling between N‐chloroamines and organoboronic acids has been developed. This new type of aminocarbonylation proceeds at mild temperatures (45–55 °C) with 2 mol % Pd/C (10 wt %) as the ligand‐free catalyst. Not only arylboronic