corresponding phthalide derivative 3 u. This synthetic method is compatible with a variety of functional groups on the aryl ring of 2. The high efficiency of the cobalt catalyst containing a dppe (dppe=1,2-bis(diphenylphosphino)ethane) ligand encouraged us to investigate the asymmetric version of the present catalytic reaction by employing bidentatechiral ligands. Thus, aromatic aldehydes 2 a-c, 2 f
We developed an efficient synthetic route for functionalized aryl-beta-C-glycosides, which are difficult to prepare by conventional methods. An aryl halide having an ester, cyano, or carbonyl group was treated with 2,4,6-triisopropylphenyllithium in the presence of a delta-lactone (Barbier-type reaction conditions) to afford a coupling product. The following deoxygenation gave the desired aryl-beta-C-glycoside in good yield. (C) 2015 Elsevier Ltd. All rights reserved.
Model studies of (+)-bergenin: A convenient formation of aryl δ-lactones
作者:Xiao-Gang Hua、Joel T. Mague、Chao-Jun Li
DOI:10.1016/s0040-4039(98)01488-9
日期:1998.9
The reaction of o-carboxyarylpropargyl bromides with aldehydes mediated by indium in aqueous medium conveniently generated aryl delta-lactones. The product formation was affected by the nature of the co-solvent. (C) 1998 Elsevier Science Ltd. All rights reserved.
The ambient temperature Ullmann reaction and its application to the total synthesis of (.+-.)-steganacin
作者:Frederick E. Ziegler、Irene Chliwner、Kerry W. Fowler、Sheldon J. Kanfer、Stephen J. Kuo、Nanda D. Sinha
DOI:10.1021/ja00522a058
日期:1980.1
Regioselective hydrostannation of highly hindered arylalkynes under ortho-directing effects
作者:Abdallah Hamze、Patrick Le Menez、Olivier Provot、Estelle Morvan、Jean-Daniel Brion、Mouâd Alami
DOI:10.1016/j.tet.2010.09.010
日期:2010.11
Palladium-catalyzed hydrostannation reactions of ortho-disubstituted arylalkynes were achieved with total stereo- and regio-selectivity in THF at room temperature. The regioselectivity was found to be under the control of the ortho-substituents (ortho-directing effects. ODE) and pure alpha-vinylstannanes are produced in good yields and as single isomers regardless of the substituents' nature. These hydrostannation alpha-products are precursors of choice for the preparation of stereo-defined triarylolefins. (C) 2010 Elsevier Ltd. All rights reserved.