Catalytic Enantioselective Synthesis of Chiral Phthalides by Efficient Reductive Cyclization of 2-Acylarylcarboxylates under Aqueous Transfer Hydrogenation Conditions
作者:Bo Zhang、Ming-Hua Xu、Guo-Qiang Lin
DOI:10.1021/ol901674k
日期:2009.10.15
A new diamine ligand for asymmetrictransferhydrogenation (ATH) was discovered. The reductive cyclization of 2-acylarylcarboxylates was found to proceed highly stereoselectively by the new Ru complex-catalyzed ATH and subsequent in situ lactonization under aqueous conditions. It enables efficient access to a wide variety of 3-substituted phthalides in enantiomericallypure form.
Hollow-Shell-Structured Nanospheres: A Recoverable Heterogeneous Catalyst for Rhodium-Catalyzed Tandem Reduction/Lactonization of Ethyl 2-Acylarylcarboxylates to Chiral Phthalides
作者:Rui Liu、Ronghua Jin、Juzeng An、Qiankun Zhao、Tanyu Cheng、Guohua Liu
DOI:10.1002/asia.201301543
日期:2014.5
Chiral organorhodium‐functionalized hollow‐shell‐structured nanospheres were prepared by immobilization of a chiral N‐sulfonylated diamine‐based organorhodium complex within an ethylene‐bridged organosilicate shell. Structural analysis and characterization reveal its well‐defined single‐site rhodium active center, and transmission electron microscopy images reveal a uniform dispersion of hollow‐shell‐structured
A Polymer-Coated Rhodium/Diamine-Functionalized Silica for Controllable Reaction Switching in Enantioselective Tandem Reduction–Lactonization of Ethyl 2-Acylarylcarboxylates
作者:Lingyu Kong、Junwei Zhao、Tanyu Cheng、Jingrong Lin、Guohua Liu
DOI:10.1021/acscatal.5b02797
日期:2016.4.1
water. At 40 °C, the catalyst promotes highly enantioselective tandem reduction–lactonization by adopting the extended form of the thermoresponsive polymer coating, whereas at 15 °C the reaction is terminated and the heterogeneous catalyst can be recycled because of its closed form. This feature endows this catalyst with high efficiency and recyclability for the synthesis of chiral phthalides in an environmentally
在不对称催化中非常需要设计用于可控反应转换的智能多相催化剂。在这项工作中,通过利用水溶性聚合物涂层的热响应性能和二氧化硅纳米颗粒的局限性,我们在涂有水溶性热响应聚合物的SiO 2纳米球上构建了具有手性铑/二胺官能度的二氧化硅材料。固态13产物的13 C NMR光谱显示在热响应性聚合物内定义明确的单中心手性铑活性中心,并且扫描电子显微镜和透射电子显微镜显示其均匀分散的形态。作为一种智能的非均相催化剂,它可以在水中进行对映选择性串联还原-内酯化2-酰基芳基羧酸乙酯的内酯化反应,从而实现基于催化剂的温度控制反应转换。在40°C下,该催化剂通过采用扩展形式的热响应性聚合物涂层,促进了高度对映选择性的串联还原-内酯化;而在15°C下,该反应因其封闭形式而终止反应,并且多相催化剂可以循环使用。
A superhydrophobic mesostructured silica as a chiral organometallic immobilization platform for heterogeneous asymmetric catalysis
作者:Bing Han、Lei Zhao、Yongkang Song、Zhongrui Zhao、Dongfeng Yang、Rui Liu、Guohua Liu
DOI:10.1039/c8cy00648b
日期:——
the hydrophobic rhodium/diamine-functionalized catalyst greatly promotes the enantioselective tandemreduction/lactonization of ethyl2-acylarylcarboxylates to afford various chiralphthalides, whereas the hydrophobic ruthenium/diamine-functionalized catalyst boosts an efficient asymmetric transfer hydrogenation-dynamic kinetic resolution process for construction of 1,2-distereocentered diethyl α-