Spiridopoulos Georgios, Kramer Markus, Kracht Felix, Maichle-Mössmer Cäcilia, Anwander Reiner
Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany.
Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany.
Chemistry. 2022 Aug 26;28(48):e202200823. doi: 10.1002/chem.202200823. Epub 2022 Jul 7.
The molecular structure of enigmatic "poly(aluminium-methyl-methylene)" (first reported in 1968) has been unraveled in a transmetalation reaction with gallium methylene [Ga (CH ) ] and AlMe . The existence of cage-like methylaluminomethylene moieties was initially suggested by the reaction of rare-earth-metallocene complex [Cp* Lu{(μ-Me) AlMe }] with excess AlMe affording the deca-aluminium cluster [Cp* Lu (μ -CH ) Al (CH ) ] in low yield (Cp*=C Me ). Treatment of [Ga (CH ) ] with excess AlMe reproducibly gave the crystalline dodeca-aluminium complex [(CH ) Al (μ -CH ) ] (MAM-12). Revisiting a previous approach to "poly(aluminium-methyl-methylene" by using a (C H ) TiCl /AlMe (1 : 100) mixture led to amorphous solids displaying solubility behavior and spectroscopic features similar to those of crystalline MAM-12. The gallium methylene-derived MAM-12 was used as an efficient methylene transfer reagent for ketones.
神秘的“聚（铝 - 甲基 - 亚甲基）”（1968年首次报道）的分子结构已在与亚甲基镓[Ga(CH₂)]和AlMe₃的金属转移反应中被解析。笼状甲基铝亚甲基部分的存在最初是由稀土金属茂络合物[Cp₂Lu{(μ-Me)AlMe₂}]与过量的AlMe₃反应提出的，该反应以低产率得到十铝簇合物[Cp₂Lu(μ-CH₂)Al₉(CH₃)₉]（Cp* = C₅Me₅）。用过量的AlMe₃处理[Ga(CH₂)]可重复性地得到结晶十二铝络合物[(CH₂)₂Al₁₂(μ-CH₂)₁₂]（MAM - 12）。重新审视以前通过使用（C₆H₅）₂TiCl₂/AlMe₃（1∶100）混合物制备“聚（铝 - 甲基 - 亚甲基）”的方法，得到了具有与结晶MAM - 12相似的溶解行为和光谱特征的无定形固体。由亚甲基镓衍生的MAM - 12被用作酮的高效亚甲基转移试剂。
