Self-association-free dimeric cinchona alkaloid organocatalysts: unprecedented catalytic activity, enantioselectivity and catalyst recyclability in dynamic kinetic resolution of racemic azlactones
作者:Ji Woong Lee、Tae Hi Ryu、Joong Suk Oh、Han Yong Bae、Hyeong Bin Jang、Choong Eui Song
DOI:10.1039/b917882a
日期:——
Self-association-free, bifunctional, squaramide-based dimeric cinchonaalkaloidorganocatalysts show unprecedented catalytic activity, enantioselectivity and catalyst recyclability in the dynamic kinetic resolution (DKR) reaction of a broad range of racemic azlactones.
A palladium(0)-catalyzed aminocarbonylationreaction employing molybdenum hexacarbonyl as a carbonmonoxide precursor for the production of N-capped amino acids using aryl and heteroaryl bromides and triflates is reported. The carbonmonoxide is formed ex situ through the use of a two-chamber system, where carbonmonoxide generated in one chamber is free to diffuse over and be consumed in the other
Palladium-catalyzed aminocarbonylation of heteroaryl halides using di-tert-butylphosphinoferrocene
作者:Bo Qu、Nizar Haddad、Zhengxu S. Han、Sonia Rodriguez、Jon C. Lorenz、Nelu Grinberg、Heewon Lee、Carl A. Busacca、DhileepKumar Krishnamurthy、Chris H. Senanayake
DOI:10.1016/j.tetlet.2009.08.065
日期:2009.11
Pd-catalyzed aminocarbonylation of heteroaryl halides, using monodentate ligand di-tert-butylphosphinoferrocene tetrafluoroborate is reported. Good to high yields were obtained with chiral amines on a variety of substrates including 2-bromo heteroaryls. (C) 2009 Elsevier Ltd. All rights reserved.
Brønsted Acid Catalyzed Dynamic Kinetic Resolution of Azlactones for the Synthesis of Aryl Glycine Derivatives
作者:Liu-Zhu Gong、Chao Wang、Hong-Wen Luo
DOI:10.1055/s-0030-1259711
日期:2011.4
The dynamic kinetic resolution of C4-aryl azlactones with alcohols was investigated by employing Brønsted acid catalysis. The reaction provided an efficient complementary approach to access chiral aryl glycine derivatives with excellent yields (up to 99%) and enantioselectivities (up to 96% ee).