由市售或合成的氨基醇制备一系列对映体纯的2- [2-(二芳基膦基)芳基]-恶唑啉。对于恶唑啉的形成,采用了三种程序:(i)与2-卤代苯甲酸一锅缩合,(ii)ZnCl 2与2-卤代苯甲腈-苯胺催化缩合,和(iii)通过2-卤代苯甲酰胺的三步顺序和甲苯磺酸盐或氯化物。通过非对映选择性亲核取代Ar 1 Ar 2 PC1的卤化物或通过LiPAr 1 Ar 2亲核芳族取代制备含有立体异构磷的膦恶唑啉。另外,制备了硫和硒类似物。
由市售或合成的氨基醇制备一系列对映体纯的2- [2-(二芳基膦基)芳基]-恶唑啉。对于恶唑啉的形成,采用了三种程序:(i)与2-卤代苯甲酸一锅缩合,(ii)ZnCl 2与2-卤代苯甲腈-苯胺催化缩合,和(iii)通过2-卤代苯甲酰胺的三步顺序和甲苯磺酸盐或氯化物。通过非对映选择性亲核取代Ar 1 Ar 2 PC1的卤化物或通过LiPAr 1 Ar 2亲核芳族取代制备含有立体异构磷的膦恶唑啉。另外,制备了硫和硒类似物。
Zwitterionic Iridium Complexes with P,N-Ligands as Catalysts for the Asymmetric Hydrogenation of Alkenes
作者:Axel Franzke、Andreas Pfaltz
DOI:10.1002/chem.201003314
日期:2011.4.4
Several zwitterionic iridium complexes based on chiralP,N‐ligands with imidazoline or oxazoline donors and anionic tetraarylborate or aryltrifluoroborate substituents have been synthesized. The corresponding cationic analogues have also been prepared, to evaluate the effect of the covalent linkage between the anion and the cationic metal complex in catalytic reactions. The respective pairs of structurally
Synthesis of new serine-based phosphinooxazoline ligands and iridium complexes for asymmetric hydrogenations
作者:Axel Franzke、Felix Voss、Andreas Pfaltz
DOI:10.1016/j.tet.2011.02.021
日期:2011.6
A series of serine-based phosphinooxazoline ligands was synthesized and the corresponding iridum complexes were successfully applied in the asymmetric hydrogenation of various unfunctionalized olefines and acetophenone-N-phenyl-imine. The results show that these new derivatives are useful substitutes for the standard tert-leucine-derived PHOX ligands. (C) 2011 Elsevier Ltd. All rights reserved.