Preston Dan, Tucker Robert A J, Garden Anna L, Crowley James D
Department of Chemistry, University of Otago , P.O. Box 56, Dunedin 9054, New Zealand.
Inorg Chem. 2016 Sep 6;55(17):8928-34. doi: 10.1021/acs.inorgchem.6b01435. Epub 2016 Aug 18.
There is continued interest in the assembly of heterometallic metallosupramolecular assemblies due to the potential for new structural types and/or interesting chemical and physical properties. Two novel methylene-linked bis-2-pyridyl-1,2,3-triazole ligands (1a, 1b) were synthesized through CuAAC "click" chemistry between dichloromethane (DCM), sodium azide, and the appropriate ethynylpyridine, giving the shortest possible "regular" bis-pyridyl-1,2,3-triazole. The first example of bis-coordination of two 2-pyridyl-1,2,3-triazoles (Rpytri) around one Pt(II) center is reported, giving exclusive formation of head-to-tail Pt(Rpytri)2 complexes with vacant binding sites suitable for complexation with other metals and the formation of heterometallic assemblies. The concentration-dependent formation of an equilibrium mixture of a heterometallic Pd2Pt2(L)4 [4 + 4] square and Pd3Pt3(L)6 [6 + 6] hexagon was observed, and at lower concentrations ([reactants] = 1.5 mM) hexamer formation was negligible. The Pt(L)2 building block could also be utilized in the synthesis of a concentration-independent Cu2Pt2(L)4 metallomacrocyle. These compounds were characterized with (1)H, (13)C, and (1)H DOSY NMR spectroscopies, elemental analysis, mass spectrometry, and in some cases X-ray crystallography.
由于具有形成新型结构类型和/或有趣化学和物理性质的潜力，人们对异金属金属超分子组装体的组装一直保持着兴趣。通过二氯甲烷（DCM）、叠氮化钠与适当的乙炔基吡啶之间的铜催化炔烃环化加成（CuAAC）“点击”化学合成了两种新型的亚甲基连接的双-2-吡啶基-1,2,3-三唑配体（1a、1b），得到了可能最短的“规则”双吡啶基-1,2,3-三唑。报道了两个2-吡啶基-1,2,3-三唑（Rpytri）围绕一个Pt（II）中心的双配位的首个实例，专一形成了头对尾的Pt（Rpytri）2配合物，其具有适合与其他金属络合的空结合位点以及异金属组装体的形成。观察到了异金属Pd2Pt2(L)4 [4 + 4]正方形和Pd3Pt3(L)6 [6 + 6]六边形的平衡混合物的浓度依赖性形成，并且在较低浓度（[反应物]=1.5 mM）下六聚体的形成可忽略不计。Pt(L)2结构单元也可用于合成浓度无关的Cu2Pt2(L)4金属大环。这些化合物通过(1)H、(13)C和(1)H DOSY NMR光谱、元素分析、质谱进行了表征，在某些情况下还通过X射线晶体学进行了表征。
