Enantioselective Borohydride Reduction Catalyzed by Optically Active Cobalt Complexes
作者:Tohru Yamada、Takushi Nagata、Kiyoaki D. Sugi、Kiyotaka Yorozu、Taketo Ikeno、Yuhki Ohtsuka、Daichi Miyazaki、Teruaki Mukaiyama
DOI:10.1002/chem.200304794
日期:2003.9.22
enantioselective borohydride reduction of aromatic ketones or imines to the corresponding alcohols was developed in the presence of a catalytic amount of an opticallyactive cobalt(II) complex catalyst. This enantioselective reduction is carried out using a precisely premodified borohydride with alcohols such as tetrahydrofurfuryl alcohol, ethanol and methanol. High optical yields are obtained by choosing
2,2-Difluoro-1,3-diketones as <i>gem</i>
-Difluoroenolate Precusors for Asymmetric Aldol Addition with <i>N</i>
-Benzylisatins
作者:Jinlong Qian、Wenbin Yi、Xin Huang、Jerry P. Jasinski、Wei Zhang
DOI:10.1002/adsc.201600392
日期:2016.9.1
2,2‐Difluoro‐1,3‐diketones are introduced as gem‐difluoroenolate precursors for the first example of an organocatalytic asymmetric aldol addition with N‐benzylisatins to form 3‐difluoroalkyl‐3‐hydroxyoxindoles.
Ag-Catalyzed Insertion of Alkynyl Carbenes into C–C Bonds of β-Ketocarbonyls: A Formal C(sp<sup>2</sup>) Insertion
作者:Yongquan Ning、Qingmin Song、Paramasivam Sivaguru、Lizuo Wu、Edward A. Anderson、Xihe Bi
DOI:10.1021/acs.orglett.1c04081
日期:2022.1.21
Here we report a silver-catalyzed alkynyl carbene insertion into β-ketocarbonyls using alkynyl N-nosylhydrazones as alkynyl carbene precursors, which provides access to trisubstituted allenyl ketones. This reaction represents the first example of an alkynyl carbene insertion into a C–C σ bond, affording products homologated with an sp2 carbon center. The products are useful substrates for further transformations
Lanthanoid complexes supported by retro-Claisen condensation products of β-triketonates
作者:Laura Abad Galán、Alexandre N. Sobolev、Eli Zysman-Colman、Mark I. Ogden、Massimiliano Massi
DOI:10.1039/c8dt03585g
日期:——
reactions, consistent with two examples that have been reported previously. The lability of the lanthanoid cations in the presence of a varying set of potential ligands gave rise to structures where one, two, or three of the molecules involved in the retro-Claisen condensation reaction were linked to the lanthanoid centres. These results, along with measurements of ligand decomposition in the presence of
Cu-Catalyzed Esterification Reaction via Aerobic Oxygenation and C–C Bond Cleavage: An Approach to α-Ketoesters
作者:Chun Zhang、Peng Feng、Ning Jiao
DOI:10.1021/ja4085463
日期:2013.10.9
The Cu-catalyzed novel aerobic oxidativeesterification reaction of 1,3-diones for the synthesis of α-ketoesters has been developed. This method combines C-C σ-bond cleavage, dioxygen activation and oxidative C-H bond functionalization, as well as provides a practical, neutral, and mild synthetic approach to α-ketoesters which are important units in many biologically active compounds and useful precursors
已开发出用于合成 α-酮酯的 Cu 催化的新型 1,3-二酮有氧氧化酯化反应。该方法结合了 CC σ-键裂解、双氧活化和氧化 CH 键功能化,并为 α-酮酯提供了一种实用、中性和温和的合成方法,α-酮酯是许多生物活性化合物中的重要单元和各种有用的前体。功能组转换。在机理研究的基础上提出了一个合理的激进过程。