Tallu Mirko, Peters Bertram, Friedrich Alexander, Dehnen Stefanie
Institute of Nanotechnology (INT), Karlsruher Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, 35043 Marburg, Germany.
Inorg Chem. 2023 Aug 28;62(34):13943-13952. doi: 10.1021/acs.inorgchem.3c01886. Epub 2023 Aug 15.
The selective methylation and butylation of chalcogenido metalate clusters by utilizing imidazolium-based ionic liquids turned out to be not only a comparably mild but at the same time also the only known method for postsynthetic alkylation of such species in order to increase their solubility. For additional impact on the crystal structures, selective alkylation with longer alkyl chains was addressed by utilizing the ionic liquid (CCIm)[BF] (C = decyl group at position 1 and C = methyl group at position 3 of the cation's Im = imidazolium ring) for ionothermal syntheses of functionalized tellurido mercurate clusters. Herein, we report three novel compounds, two of which comprise cluster anions that exhibit a selective organic functionalization of their terminal telluride ligands upon in situ alkylation with the ionic liquid: [HgTe(Te)(TeDec)] (in ; Dec = decyl) represents the first decylated chalcogenido metalate cluster. A unique heteroleptic functionalization, combining methylation and decylation, was achieved for the second cluster, [HgTe(Te)(TeDec)(TeMe)] (in ; Me = methyl). The third cluster is purely inorganic, but based on the same cluster core architecture: [HgTe(Te)(Te)] (in ) comprises a tritelluride unit instead of two HgTeR groups (R = Me, Dec). As a consequence of the long alkyl chains, both at the cluster and at the charge-compensating cations, all three crystal structures are characterized by lamellar assemblies of cations and anions. For further comparison of the properties of the organometallic versus purely inorganic compounds, vibrational and optical properties of crystalline samples of the compounds comprising clusters and were studied by means of infrared, Raman, and UV-visible spectroscopy. The results clearly show the effect of the presence of an organic decoration (in ) relative to its absence (in ), reflected by a red shift of the band gap energy ( → ) and a replacement of the Te-C bands (in ) with bands for tritelluride units (in ).
利用基于咪唑鎓的离子液体对硫属金属酸盐簇进行选择性甲基化和丁基化，结果表明这不仅是一种相对温和的方法，同时也是目前已知的唯一一种用于此类物质合成后烷基化以提高其溶解度的方法。为了对晶体结构产生额外影响，通过使用离子液体(CCIm)[BF]（阳离子的Im = 咪唑环中位置1处的C = 癸基且位置3处的C = 甲基）进行离子热合成功能化碲基汞酸盐簇，研究了用更长烷基链进行的选择性烷基化。在此，我们报道了三种新型化合物，其中两种包含簇阴离子，在用离子液体原位烷基化后，其末端碲化物配体表现出选择性有机官能化：[HgTe(Te)(TeDec)]（在……中；Dec = 癸基）代表首个癸基化的硫属金属酸盐簇。对于第二个簇[HgTe(Te)(TeDec)(TeMe)]（在……中；Me = 甲基），实现了甲基化和癸基化相结合的独特杂配体官能化。第三个簇是纯无机的，但基于相同的簇核结构：[HgTe(Te)(Te)]（在……中）包含一个三碲化物单元而非两个HgTeR基团（R = Me, Dec）。由于簇和电荷补偿阳离子上都存在长烷基链，所有三种晶体结构的特征都是阳离子和阴离子的层状组装。为了进一步比较有机金属化合物与纯无机化合物的性质，通过红外、拉曼和紫外 - 可见光谱研究了包含簇……和……的化合物晶体样品的振动和光学性质。结果清楚地表明了有机修饰存在（在……中）相对于不存在（在……中）的影响，表现为带隙能量的红移（……→……）以及用三碲化物单元的谱带（在……中）取代Te - C谱带（在……中）。
