Studies on pyrimidine-annelated heterocycles: synthesis of novel pyrazolo[3′,4′:4,5]pyrido[2,3-d]pyrimidines by intramolecular 1,3-dipolar cycloadditions
摘要:
Suitably functionalised 1,3-substituted 6-chloro-1,2,3,4-tetrahydro-2,4-dioxopyrimidine-5-carbaldehydes 3a-1 cyclise intramolecularly to yield novel furo- and thieno-[2 '',3 '':4',5']pyrazolo[3',4':4,5]pyrido-[2,3-d]pyrimidines 8a-1 in fair to good yields together with the pyrazolopyrimidines 7 as side products. Remarkably, this synthesis not only left the pyrimidine nucleus unaffected but also gave no dimer formation.
Efficient alkylations of amines by alcohols catalyzed by well-defined Co(II) complexes are described that are stabilized by a PCP ligand (N,N′-bis(diisopropylphosphino)-N,N′-dimethyl-1,3-diaminobenzene) based on the 1,3-diaminobenzene scaffold. This reaction is an environmentally benign process implementing inexpensive, earth-abundant nonprecious metal catalysts and is based on the acceptorless alcohol
Divergent Coupling of Alcohols and Amines Catalyzed by Isoelectronic Hydride Mn<sup>I</sup>and Fe<sup>II</sup>PNP Pincer Complexes
作者:Matthias Mastalir、Mathias Glatz、Nikolaus Gorgas、Berthold Stöger、Ernst Pittenauer、Günter Allmaier、Luis F. Veiros、Karl Kirchner
DOI:10.1002/chem.201603148
日期:2016.8.22
Herein, we describe an efficient coupling of alcohols and aminescatalyzed by well‐defined isoelectronic hydride MnI and FeII complexes, which are stabilized by a PNP ligand based on the 2,6‐diaminopyridine scaffold. This reaction is an environmentally benign process implementing inexpensive, earth‐abundant non‐precious metal catalysts, and is based on the acceptorless alcohol dehydrogenation concept
A series of well‐defined iron(II) complexes of the types [Fe(PNP)Br2] and [Fe(PNP)(CO)Br2] with PNPpincer ligands based on triazine and pyridine backbones were prepared and fully characterized. These complexes were tested as catalysts for the alkylation of amines by alcohols. The high‐spin complexes [Fe(PNP)Br2] are catalytically inactive. The low‐spin complexes [Fe(PNP)(CO)Br2] bearing a carbonyl
Visible-light-induced photoxidation-Povarov cascade reaction: synthesis of 2-arylquinoline through alcohol and <i>N</i>-benzylanilines under mild conditions <i>via</i> Ag/g-C<sub>3</sub>N<sub>4</sub> nanometric semiconductor catalyst
作者:Peng Wang、Xiaowen Wang、Xiyu Niu、Li Zhu、Xiaoquan Yao
DOI:10.1039/d0cc00885k
日期:——
Ag/g-C3N4 nanometric semiconductor as the photocatalyst, 2-arylquinolines were synthesized through a photoxidation-Povarov cascade reaction of N-benzylanilines and alcohols under visible lightirradiation. Under the blue light of a 3 W LED, good yields were achieved for various substrates in oxygen at room temperature. This methodology provides a green and mild alternative for the formation of 2-arylquinoline
以Ag / g-C3N4纳米半导体为光催化剂,在可见光照射下,通过N-苄基苯胺和醇的光氧化-Povarov级联反应合成了2-芳基喹啉。在3 W LED的蓝光下,室温下在氧气中各种衬底的产率都很高。该方法为2-芳基喹啉衍生物的形成提供了绿色和温和的替代方法。值得注意的是,Ag / g-C3N4纳米复合材料可以方便地回收并以令人满意的产率重复使用数次。
作者:Jan Pecak、Berthold Stöger、Matthias Mastalir、Luis F. Veiros、Liliana P. Ferreira、Marc Pignitter、Wolfgang Linert、Karl Kirchner
DOI:10.1021/acs.inorgchem.9b00235
日期:2019.4.1
characterization of air-stable cationic mono nitrosonium Fe(I) PNP pincer complexes of the type [Fe(PNP)(NO)Cl]+ are described. These complexes are obtained via direct nitroslyation of [Fe(PNP)Cl2] with nitric oxide at ambient pressure. On the basis of magnetic and EPR measurements as well as DFT calculations, these compounds were found to adopt a low-spin d7 configuration and feature a nearly linear bound NO ligand
描述了[Fe(PNP)(NO)Cl] +类型的空气稳定型阳离子单硝铁Fe(I)PNP钳形配合物的合成和表征。这些配合物是通过在环境压力下将一氧化氮直接[Fe(PNP)Cl 2 ]亚硝化而获得的。根据磁性和EPR测量以及DFT计算,发现这些化合物采用低自旋d 7构型,并具有几乎呈线性键合的NO配体,表明具有Fe I NO +而不是Fe II NO •性质。介绍了所有硝化铁(I)PNP配合物的X射线结构。初步调查显示[Fe(PNP NH - iPr)(NO)(Cl)] +有效催化伯醇与芳族胺和苄基胺的转化,从而以良好的分离产率生成单N-烷基化胺。