已经制备了许多钯(II)和铂(II)双螯合物,它们含有一种对称或不对称的β-二酮阴离子,或包含两种不同的β-二酮阴离子。顺式和反式异构体在不对称 β-二酮二元螯合物的溶液中的存在通过 1H 和 13C NMR 光谱证实。钯 (II) 配合物在溶液中达到平衡的几何异构化速度很快,而铂 (II) 配合物非常惰性。混合配体螯合物在溶液中稳定,没有歧化迹象。双(1-苯基-1,3-丁二酮)钯(II)、双(2,4-己二酮)钯(II)和双(1,1,1-三氟-2,4-戊二酮)的异构体对) 铂 (II) 被分离出来,第一个复合物的顺式异构体的分子结构通过 X 射线分析确定。
Comprehensive SummaryPd‐mediated bioorthogonal cleavage reactions have been extensively utilized in the activation of prodrug molecules, precise regulation of protein function, and cellular engineering. However, the availability of cleavable "caging" groups is quite limited, and their application in nucleic acid modification has seldom been reported. Herein, we introduce a method based on Pd‐catalyzed reduction amination of azides as a decaging strategy to activate the activity of biomolecules. We designed modifications on the bioactive sites with azides or their derivatives to mask the related biological function, followed by the release of biological activity through Pd‐catalyzed NaBH4 reduction amination reaction. This study has demonstrated that the strategy can effectively be used to activate bioactive molecules such as fluorescent probes, prodrugs, and to regulate the biological function of RNA, including reverse transcription extension, binding to ligands, and cleavage activity of the CRISPR‐Cas system. All results confirm that this strategy provides an efficient and controllable "OFF to ON" biological switch, capable of achieving significant regulatory effects substoichiometrically, and is expected to be extended to other biological applications.
Palladacycles of unsymmetrical (N,C<sup>−</sup>,E) (E = S/Se) pincers based on indole: their synthesis, structure and application in the catalysis of Heck coupling and allylation of aldehydes
作者:Mahabir P. Singh、Fariha Saleem、Gyandshwar K. Rao、S. Kumar、Hemant Joshi、Ajai K. Singh
DOI:10.1039/c6dt00060f
日期:——
[Pd(L1/L2–H)Cl] (1/2), where they bind in a tridentate (N,C−,E) mode. L1 and L2, their aldehyde precursors and Pd(II)-complexes, 1 and 2, have been characterized by 1H, 13C1H} and 77Se1H} NMR and HR-MS. Palladium(II) complexes 1 and 2 and precursor aldehydes of L1 and L2 were verified using single crystal X-ray diffraction. The catalytic activities of complexes 1 and 2 were investigated for Heck coupling
通过1-(2-苯基硫烷基/硒代乙基)-1 H的缩合反应,首次合成具有吲哚核的不对称(N,C,E)型钳位配体前体[ L1和L2:E = S / Se] -吲哚-3-甲醛与苄胺。合成规程很容易,并且收率很高(> 85%)。L1和L2与四氯钯钠(反应II在CH存在下)3 COONa结果在配合物[钯(L1 / L2 -H)CL](1 / 2),在那里它们结合在三齿(N,C - ,E)模式。L1和L2,其醛前体和Pd(II)配合物1和2的特征在于1 H,13 C 1 H}和77 Se 1 H} NMR和HR-MS。使用单晶X射线衍射验证了钯(II)配合物1和2以及L1和L2的前体醛。研究了配合物1和2的催化活性,以进行醛的Heck偶联和烯丙基化。这两个反应分别需要配合物负载量为0.1–0.3和1 mol%。
Controlled interaction of benzaldehyde thiosemicarbazones with palladium: formation of bis-complexes with cis-geometry and organopalladium complexes, and their catalytic application in C–C and C–N coupling
作者:Jayita Dutta、Samaresh Bhattacharya
DOI:10.1039/c3ra40829a
日期:——
coordinated to palladium, via dissociation of the acidic proton and activation of an ortho C–H bond, as dianionic tridentate C,N,S-donors forming two adjacent five-membered chelate rings. The [Pd(NS–R)2] and [Pd(CNS–R)(PPh3)] complexes show characteristic 1H NMR signals, and in dichloromethane solution they all display intense absorptions in the visible and ultraviolet regions. The [Pd(NS–R)2] and [Pd(CNS–R)(PPh3)]
4-R-苯甲醛硫代半碳酮(R = OCH 3,CH 3,H,Cl和NO 2)的1:1混合物与2-吡啶甲酸在相对温和的回流条件下,在乙醇介质中加入等量的Na 2 [PdCl 4 ],得到一组主要产品为[Pd(NS–R)2 ]的配合物,以及另一种类型的Pd (CNS–R)} n ]作为次要产品(其中NS–R和CNS–R分别表示N,S-和C,N,S配位的硫代半乳糖胺)。[Pd(CNS–R)} n ]络合物可以通过长时间回流下进行的类似反应方便地以高收率获得。[Pd(CNS–R)} n ]络合物中的硫桥在与三苯膦得到[Pd(CNS–R)(PPh 3)]类型的配合物。[Pd(NS-OCH 3)2 ],[Pd(NS-CH 3)2 ],[Pd(NS-Cl)2 ],[Pd(CNS-CH 3)(PPh 3)],[确定了Pd(CNS–H)(PPh 3)]和[Pd(CNS–Cl)(PPh 3)]。在[Pd(NS–R)2
Application of the Fluorous Biphase Concept to Palladium-CatalyzedSuzuki Couplings
Suzuki C−C couplings were performed in high yields in a fluorousbiphase system applying the four differently perfluoro-tagged Pd complexes 2a – d. All four complexes showed similar catalytic activities in the coupling of electron-rich or electron-deficient bromoarenes 3a – e and arylboronic acids 4a – c (Tables 1 and 2). Furthermore, we were able to show that all four Pd complexes could be recycled
Nucleic acid interaction and antibacterial behaviours of a ternary palladium(II) complexes
作者:Mohan N. Patel、Promise A. Dosi、Bhupesh S. Bhatt
DOI:10.1016/j.saa.2011.10.077
日期:2012.2
The bidentate ligands and Pd(II) complexes have been synthesized and characterized using elemental analysis (C, H, N), (1)H NMR, (13)C NMR, electronic spectra, FT-IR and FAB mass spectroscopy. The binding of palladiumcomplexes with calf thymus DNA (CT DNA) has been explored using absorption titration, DNA melting temperature and viscosity measurements. The cleavage reaction on pUC19 DNA has been monitored
Allyl palladium dithiocarbamates and related dithiolate complexes as precursors to palladium sulfides
作者:Anthony Birri、Benjamin Harvey、Graeme Hogarth、Elif Subasi、Fadime Uğur
DOI:10.1016/j.jorganchem.2007.02.015
日期:2007.5
Allyl-palladium dithiocarbamate complexes, [Pd(allyl)(S2CNR2)], have been prepared from the addition of dithiocarbamate salts to [Pd(allyl)(μ-Cl)]2 and TGA and DSC studies have been carried out in order to assess their potential as MOCVD precursors to palladium sulfides. For comparison [(η3-C4H7)Pd(S2PPh2)] and [Pd(S2CNMeR)2] (R = Bu, Hex) have also been prepared and tested as precursors. The unsymmetrical