21462-02-2Relevant articles and documents
Cyclosophoraose as a catalytic carbohydrate for methanolysis
Lee, Sanghoo,Jung, Seunho
, p. 461 - 468 (2004)
A novel catalytic methanolysis can be induced by a natural cyclooligosaccharide, a cyclosophoraose (cyclic-(1→2)-β-D-glucan, Cys), which is a member of a family of unbranched cyclooligosaccharides produced as intra- or extraoligosaccharides by soil microorganisms of the genus, Rhizobium. Cys catalyzed the methanolysis for 5(4H)-oxazolones and various phospholipids. Cys enhanced the methanolysis reaction about 9200-fold for a benzylidene oxazolone or 250-fold for dipalmitoylphosphatidylcholine comparing with control. In this study, we describe that natural cyclosophoraoses isolated from the Rhizobium species function as catalytic carbohydrates for the methanolysis.
Nickel-Catalyzed Asymmetric Hydrogenation of 2-Amidoacrylates
Chen, Jianzhong,Gridnev, Ilya D.,Hu, Yawen,Li, Bowen,Zhang, Wanbin,Zhang, Zhenfeng
supporting information, p. 5371 - 5375 (2020/02/15)
Earth-abundant nickel, coordinated with a suitable chiral bisphosphine ligand, was found to be an efficient catalyst for the asymmetric hydrogenation of 2-amidoacrylates, affording the chiral α-amino acid esters in quantitative yields and excellent enantioselectivity (up to 96 % ee). The active catalyst component was studied by NMR and HRMS, which helped us to realize high catalytic efficiency on a gram scale with a low catalyst loading (S/C=2000). The hydrogenated products could be simply converted into chiral α-amino acids, β-amino alcohols, and their bioactive derivatives. Furthermore, the catalytic mechanism was investigated using deuterium-labeling experiments and computational calculations.
Reactivity of unsaturated 5(4H)-oxazolones with Hg(II) acetate: Synthesis of methyl N-benzoylamino-3-arylacrylates
Roiban, Gheorghe-Doru,Soler, Tatiana,Contel, Maria,Grosu, Ion,Cativiela, Carlos,Urriolabeitia, Esteban P.
experimental part, p. 195 - 203 (2011/10/31)
An efficient and high-yield procedure to prepare methyl N-benzoylamino-3-arylacrylates from unsaturated (Z)-2-aryl-4-arylidene-5-(4H)- oxazolones and Hg(OAc)2 in methanol is described herein. The observed reactivity of mercury(II) acetate here