Catalytic oxidation of alcohols with novel non-heme <i>N</i><sub>4</sub>-tetradentate manganese(<scp>ii</scp>) complexes
作者:Vincent Vermaak、Desmond A. Young、Andrew J. Swarts
DOI:10.1039/c8dt03808b
日期:——
non-heme N4-tetradentate Mn(OTf)2 complexes of the type, [(L)MnOTf2], where L = R,R and S,S enantiomers of BPMCN, its 6-methyl and 6-bromo derivatives as well as the novel ligand BMIMCN (BPMCN = N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)-(R,R/S,S)-1,2-diaminocyclohexane, BMIMCN = N,N′-dimethyl-N,N′-bis(1-methyl-2-imidazolemethyl)-(R,R/S,S)-1,2-diaminocyclohexane). Solid state structural analysis of the BMIMCN-ligated
Manganese complexes with non-porphyrin N<sub>4</sub>ligands as recyclable catalyst for the asymmetric epoxidation of olefins
作者:Nabin Ch. Maity、Prasanta Kumar Bera、Debashis Ghosh、Sayed H. R. Abdi、Rukhsana I. Kureshy、Noor-ul H. Khan、Hari C. Bajaj、E. Suresh
DOI:10.1039/c3cy00528c
日期:——
complexes of N4 ligands derived from 2-acetylpyridine were prepared and used as catalysts in the enantioselectiveepoxidation of olefins, using H2O2 as an oxidant to give epoxides, with excellent conversions (up to 99%) and enantiomeric excess (up to 88%) within 1 h at 0 °C. A detailed mechanistic study was undertaken based on the information obtained by single crystal X-ray, optical rotation, UV-Vis
制备了由2-乙酰基吡啶衍生的N 4配体的新手性锰配合物,并用作烯烃的对映选择性环氧化的催化剂,使用H 2 O 2作为氧化剂生成环氧化物,具有优异的转化率(高达99%)和对映体过量(最高88%)在0°C下1小时内。根据单晶X射线,旋光,UV-Vis,CD光谱和动力学研究获得的信息进行了详细的机理研究,结果表明该反应对于催化剂和氧化剂的浓度是一阶的,并且是独立的。底物浓度。配合物(0.1 mol%)已成功进行了3个循环的苯乙烯与H 2 O环氧化的可循环性实验2在0°C时作为氧化剂和乙酸作为添加剂,并保持了性能。
Synthesis and Evaluation of Conformationally Restricted N4-Tetradentate Ligands for Implementation in An(III)/Ln(III) Separations
作者:Mark D. Ogden、G. Patrick Meier、Kenneth L. Nash
DOI:10.1007/s10953-011-9784-1
日期:2012.1
atoms softer than oxygen are effective for separating trivalent lanthanides (Ln(III)) from trivalentactinides (An(III)) (Nash, K.L., in: Gschneider, K.A. Jr., et al. (eds.) Handbook on the Physics and Chemistry of Rare Earths, vol. 18—Lanthanides/ActinidesChemistry, pp. 197–238. Elsevier Science, Amsterdam, 1994). It has also been shown that ligands that “restrict” their donor groups in a favorable geometry
先前的文献表明,比氧软的供体原子可有效地将三价镧系元素 (Ln(III)) 与三价锕系元素 (An(III)) 分离(Nash, KL, in: Gschneider, KA Jr., et al. (eds. ) 稀土物理和化学手册,第 18 卷—镧系元素/锕系元素化学,第 197-238 页。Elsevier Science,阿姆斯特丹,1994 年)。还表明,以有利的几何形状“限制”其供体基团的配体,适合于阳离子的空间要求,具有增加的结合亲和力。已经合成了一系列具有增加的空间“极限”的四齿含氮配体。这些配体的 pKa 值已使用电位滴定法测定,并且有色铜 (II) 配合物的形成已被用作确定配体在有机相和水相之间分配的方法。2-甲基吡啶基取代的胺配体的结果令人鼓舞,但 2-甲基吡啶基取代的二亚胺的结果表明,由于水解,这些配体不适合在溶剂萃取系统中实施。
[EN] PROCESS FOR PREPARING AMINOTETRAHYDROPYRANS<br/>[FR] PROCÉDÉ DE PRÉPARATION D'AMINOTÉTRAHYDROPYRANES
申请人:F I S - FABBRICA ITALIANA SINTETICI S P A
公开号:WO2017093209A1
公开(公告)日:2017-06-08
The present invention relates to a process for preparing 3-amino tetrahydropyrans and, more particularly, to an improved method for synthesizing a 2,3,5-substituted tetrahydropyran derivative, intermediate being used in the preparation of dipeptidyl peptidase-IV enzyme inhibitors (DPP-4 inhibitors).
Nickel-Catalyzed Asymmetric <i>C</i>-Alkylation of Nitroalkanes: Synthesis of Enantioenriched β-Nitroamides
作者:Vijayarajan Devannah、Rajgopal Sharma、Donald A. Watson
DOI:10.1021/jacs.9b04175
日期:2019.5.29
A general catalytic method for asymmetric C-alkylation of nitroalkanes using nickel catalysis is described. This method enables the formation of highly enantioenriched β-nitroamides from readily available α-bromoamides using mild reaction conditions that are compatible with a wide range of functional groups. When combined with subsequent reactions, this method allows access to highly enantioenriched