A practical synthesis of substituted 2,6-diaminopyridines via microwave-assisted copper-catalyzed amination of halopyridines
作者:Matthias Mastalir、Egon E. Rosenberg、Karl Kirchner
DOI:10.1016/j.tet.2015.08.042
日期:2015.10
selective substitution of one or two halogens by aryl or alkylamines was achieved within 2–6 h with temperatures between 80 and 225 °C affording 2,6-diaminopyridines in good to excellent isolated yields. The reaction allows easy variation between educts and different N-substitutions. The target compounds are valuable precursors for the synthesis of bis-phosphorylated 2,6-diaminopyridines which are
High-spin iron(II) complexes with mono-phosphorylated 2,6-diaminopyridine ligands
作者:Christan Schröder-Holzhacker、Berthold Stöger、Ernst Pittenauer、Günther Allmaier、Luis F. Veiros、Karl Kirchner
DOI:10.1007/s00706-016-1731-9
日期:2016.9
PNNHMe-iPr and PNNHEt-iPr a phosphine transfer reaction of a second PN ligand took place to yield the known PNP pincer complexes [Fe(κ3 P,N,P-PNPMe-iPr)Cl2] and [Fe(κ3 P,N,P-PNPEt-iPr)Cl2]. The four-coordinate complexes [Fe(κ2 P,N-PNNH2-iPr)Cl2] and [Fe(κ2 P,N-PNNH2-tBu)Cl2] did not react with CO and the formation of iron PNC pincer complexes was not observed. The reason for the reluctance to add CO was investigated
摘要通过处理制备了几个新的带有P i Pr 2和P t Bu 2单元的单磷酸化2,6-二氨基吡啶配体(PN NH2 - i Pr,PN NH2 - t Bu,PN NHMe - i Pr和PN NHEt - i Pr)。在碱的存在下,将各自的2,6-二氨基吡啶与氯膦P i Pr 2 Cl和P t Bu 2 Cl进行反应。无水的FeCl治疗2与1个当量的这些提供的四配位配位不饱和14E -配合物的[Fe(κ 2 P,N -PN NH2 -我PR)氯2 ]和[Fe(上κ 2 P,N -PN NH2 -吨丁基)氯2 ],而与PN NHMe -我Pr和PN NHEt -我镨的第二PN的膦转移反应的配体发生以产生已知的PNP钳形络合物的[Fe(κ 3 P,N,P -pnp我-我PR)氯2 ]和[Fe(上κ 3 P,N, P -PNP Et - i Pr)Cl 2]。四坐标络合物的[Fe(κ 2 P,N
Synthesis and Reactivity of Bis(silylene)‐Coordinated Calcium and Divalent Lanthanide Complexes
作者:Xiaofei Sun、Thomas Simler、Kevin Reiter、Florian Weigend、Peter W. Roesky
DOI:10.1002/chem.202003417
日期:2020.11.20
Divalent lanthanide complexes of Eu (1) and Yb (2) coordinated by a chelating pyridine‐based bis(silylene) ligand were isolated and fully characterized. Compared to the EuII complex 1, the YbII complex 2 presents a lower thermal stability, resulting in the activation of one SiII−N bond and formation of an YbIII complex (3), which features a unique silylene‐pyridyl‐amido ligand. The different thermal
分离并充分表征了由螯合吡啶基双(亚硅基)配体配位的 Eu ( 1 ) 和 Yb ( 2 ) 的二价镧系元素络合物。与Eu II配合物 1相比,Yb II配合物 2表现出较低的热稳定性,导致一个Si II -N键被激活并形成Yb III配合物(3),其具有独特的亚硅基-吡啶基-酰胺基配体。1和2的不同热稳定性指向双(亚硅基)配体的一个 Si II -N 键的还原诱导断裂。在低温下成功分离出相应的氧化还原惰性双(亚甲硅基)Ca II配合物(5 ),并鉴定出热分解为带有相同亚硅基-吡啶基-酰胺配体的Ca II配合物(4)。在这种情况下,热解反应通过另一种非氧化还原诱导的机制进行。通过原位生成的亚硅基-吡啶基-胺前配体开发了另一种更高产率的4路线。
Fully Tin‐Coated Coinage Metal Ions: A Pincer‐Type Bis‐stannylene Ligand for Exclusive Tetrahedral Complexation
作者:Frederic Krätschmer、Xiaofei Sun、Sebastian Gillhuber、Hannes Kucher、Yannick J. Franzke、Florian Weigend、Peter W. Roesky
DOI:10.1002/chem.202203583
日期:——
Tin shines better with gold or silver: A luminescent pincer-type bis-stannylene ligand for exclusive tetrahedral coordination of the coinagemetals was designed, and photoluminescence investigations as well as extensive quantum chemical calculations were carried out.
Palladium-Mediated Bis-Arylation of Inactivated and Activated Arenes
作者:Krishna C. Majumdar、Nirupam De、Santanu Chakravorty
DOI:10.1080/00397910903531870
日期:2010.12.21
A simple synthetic protocol has been developed for the bis-arylation of unactivated and activated arenes by the implementation of a palladium-catalyzed intramolecular cyclization strategy. The activated arenes give either linearly fused or angularly fused bis-cyclized product depending upon the substitutent present on the nitrogen atom, whereas inactivated arenes give only linearly fused product. The reaction has been carried out in two steps under ligand-free conditions.