Substrate-Induced Covalent Assembly of a Chemzyme and Crystallographic Characterization of a Chemzyme−Substrate Complex
作者:Gang Hu、Anil K. Gupta、Rui H. Huang、Munmun Mukherjee、William D. Wulff
DOI:10.1021/ja1070224
日期:2010.10.20
A substrate induced covalent assembly of a highly organized chemzyme known to be effective in both catalytic asymmetric aziridination and aza Diels-Alder reactions is described and the information gained from which led to an efficient one-pot aziridination protocol. The crystal structures of two chemzyme-iminium complexes were elucidated by X-ray diffraction analysis that provides critical insights into the binding of the substrates with the chemzyme.
Multicomponent Catalytic Asymmetric Aziridination of Aldehydes
作者:Anil K. Gupta、Munmun Mukherjee、William D. Wulff
DOI:10.1021/ol202472z
日期:2011.11.4
The first multicomponent catalytic asymmetric aziridination reaction is developed to give aziridine-2-carboxylic esters with very high diastereo- and enantioselectivity from aromatic and aliphatic aldehydes. This new method pushes the boundary of the aziridination reaction to substrates that failed with preformed imines.
Seeking Passe-Partout in the Catalytic Asymmetric Aziridination of Imines: Evolving Toward Substrate Generality for a Single Chemzyme
作者:Munmun Mukherjee、Anil K. Gupta、Zhenjie Lu、Yu Zhang、William D. Wulff
DOI:10.1021/jo101160c
日期:2010.8.20
The asymmetriccatalyticaziridination reaction (AZ reaction) of imines derived from dianisylmethyl (DAM) amine and tetra-methyldianisylmethyl (MEDAM) amine were examined with boroxinate catalysts preparedfrom both the VANOL and VAPOL ligands. This included an evaluation of different protocols for the preparation of the catalyst. The AZ reaction of DAM and MEDAM iminespreparedfrom nine different
衍生自亚胺的不对称催化反应氮杂环丙烷(AZ反应)d我一个nisyl米乙基(DAM)胺和四-我THYL d我一个nisyl米乙基(MEDAM)胺用由VANOL和VAPOL配体制备的硼恶烷酸酯催化剂检测。这包括对制备催化剂的不同方案的评估。检查了由9种不同的芳基和脂族醛制得的DAM和MEDAM亚胺的AZ反应。在AZ反应中,MEDAM亚胺优于DAM亚胺,具有更高的不对称诱导和更高的氮丙啶总产率。所述MEDAM亚胺发现也优于先前研究的二苯基甲基(二苯甲基或BH)和四-叔- BU TYL d我一个nisyl米乙基(BUDAM)亚胺,尤其适用于衍生自脂族醛的亚胺。在研究的九种不同的MEDAM亚胺上,平均不对称诱导率为VAPOL催化剂为ee的97%,VANOL催化剂为ee的96%。在所有情况下,除某些富电子芳基醛外,均可将MEDAM亚胺去保护成N -H氮丙啶。MEDAM亚胺比二苯甲基亚胺具有更高的反应性
Multifaceted interception of 2-chloro-2-oxoacetic anhydrides: a catalytic asymmetric synthesis of β-lactams
作者:Li Huang、Wenjun Zhao、Richard J. Staples、William D. Wulff
DOI:10.1039/c2sc21240d
日期:——
N-carboxyanhydrides or β-lactams depending on the nature of the substituent at the 3-position. All substrates can be diverted to β-lactams upon treatment with a Vilsmeier reagent. The three to four membered ring expansion is stereospecific and proceeds with high yields and diastereoselection. This method provides for an asymmetricsynthesis of β-lactams from simple aldehydes via a multi-component catalytic asymmetric