A New Protocol for the In Situ Generation of Aromatic, Heteroaromatic, and Unsaturated Diazo Compounds and Its Application in Catalytic and Asymmetric Epoxidation of Carbonyl Compounds. Extensive Studies To Map Out Scope and Limitations, and Rationalization of Diastereo- and Enantioselectivities
作者:Varinder K. Aggarwal、Emma Alonso、Imhyuck Bae、George Hynd、Kevin M. Lydon、Matthew J. Palmer、Mamta Patel、Marina Porcelloni、Jeffery Richardson、Rachel A. Stenson、John R. Studley、Jean-Luc Vasse、Caroline L. Winn
DOI:10.1021/ja034606+
日期:2003.9.1
a general process for the in situ generation of diazo compounds from tosylhydrazone sodium salts has been established and applied in sulfur-ylide mediated epoxidation reactions. The chiral, camphor-derived, [2.2.1] bicyclic sulfide 7 was employed (at 5-20 mol % loading) to render the above processes asymmetric with a range of carbonyl compounds and tosylhydrazone sodium salts. Benzaldehyde tosylhydrazone
Convenient Method for Epoxidation of Alkenes Using Aqueous Hydrogen Peroxide
作者:Man Kin Tse、Markus Klawonn、Santosh Bhor、Christian Döbler、Gopinathan Anilkumar、Herbert Hugl、Wolfgang Mägerlein、Matthias Beller
DOI:10.1021/ol047604i
日期:2005.3.1
[reaction: see text] The complex [Ru(tpy)(pydic)] (1a) is an active catalyst for epoxidation of alkenes by aqueous 30% hydrogenperoxide in tertiary alcohols. The protocol is simple to operate and gives the corresponding epoxides in good to excellent yields. Chiral enantiopure [Ru(tpy)(pydic)] complexes have been synthesized and successfully applied in this procedure.
Synthetic, spectral and catalytic activity studies of ruthenium bipyridine and terpyridine complexes: Implications in the mechanism of the ruthenium(pyridine-2,6-bisoxazoline)(pyridine-2,6-dicarboxylate)-catalyzed asymmetric epoxidation of olefins utilizing H2O2
作者:Man Kin Tse、Haijun Jiao、Gopinathan Anilkumar、Bianca Bitterlich、Feyissa Gadissa Gelalcha、Matthias Beller
DOI:10.1016/j.jorganchem.2005.12.069
日期:2006.10
6-[(4S)-4-phenyl-4,5-dihydro-oxazol-2-yl]-[2,2′]bipyridinyl new insights on the reaction intermediates and reaction pathway of the ruthenium-catalyzed enantioselectiveepoxidation are proposed. In addition, a simplified protocol for epoxidation of olefins using urea hydrogenperoxide complex as oxidizing agent has been developed.
各种Ru(L 1)(L 2)(1)配合物(L 1 = 2,2'-联吡啶,2,2':6',2''-吡啶,6-(4 S)-4-苯基-4 ,5-二氢-恶唑-2-基-2,2'-联吡啶基或2,2'-联吡啶基-6-羧酸酯; L 2 =吡啶-2,6-二羧酸酯,吡啶-2-羧酸吡啶或2,2' -联吡啶基-6-羧酸盐)(已合成(或原位生成)),并使用30%的H 2 O 2水溶液对烯烃进行环氧化测试。含有2,6-二羧酸吡啶的配合物显示出极高的催化活性。基于包含非外消旋2,2'-联吡啶(包括6-[(4 S)-4-苯基-4,5-二氢-恶唑-2-基]-[2,2']联吡啶基对钌催化的对映选择性环氧化反应的中间体和反应途径提出了新的见解。另外,已经开发出使用过氧化氢脲配合物作为氧化剂的烯烃环氧化的简化方案。
Process for the ruthenium-catalysed epoxidation of olefins by means of hydrogen peroxide
申请人:Magerlein Wolfgang
公开号:US20060161011A1
公开(公告)日:2006-07-20
The present invention relates to a process for the epoxidation of olefins using catalysts based on ruthenium complexes in the presence of hydrogen peroxide.
Structural and conformational analysis of 1-oxaspiro[2.5]octane and 1-oxa-2-azaspiro[2.5]octane derivatives by 1H, 13C, and 15N NMR
作者:Rubén Montalvo-González、Armando Ariza-Castolo
DOI:10.1002/mrc.3792
日期:2012.1
A structural and conformational analysis of 1-oxaspiro[2.5]octane and 1-oxa-2-azaspiro[2.5]octane derivatives was performed using (1) H, (13) C, and (15) N NMR spectroscopy. The relative configuration and preferred conformations were determined by analyzing the homonuclear coupling constants and chemical shifts of the protons and carbon atoms in the aliphatic rings. These parameters directly reflected