Pan Fuxing, Guggolz Lukas, Weigend Florian, Dehnen Stefanie
Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften (WZMW), Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043, Marburg, Germany.
Angew Chem Int Ed Engl. 2020 Sep 14;59(38):16638-16643. doi: 10.1002/anie.202008108. Epub 2020 Aug 4.
The Zintl anion (Ge As ) represents an isostructural and isoelectronic binary counterpart of yellow arsenic, yet without being studied with the same intensity so far. Upon introducing [(PPh )AuMe] into the 1,2-diaminoethane (en) solution of (Ge As ) , the heterometallic cluster anion [Au (Ge As)(Ge As ) ] is obtained as its salt [K(crypt-222)] [Au (Ge As)(Ge As ) ]⋅en⋅2 tol (1). The anion represents a rare example of a superpolyhedral Zintl cluster, and it comprises the largest number of Au atoms relative to main group (semi)metal atoms in such clusters. The overall supertetrahedral structure is based on a (non-bonding) octahedron of six Au atoms that is face-capped by four (Ge As ) (x=2, 3) units. The Au atoms bind to four main group atoms in a rectangular manner, and this way hold the four units together to form this unprecedented architecture. The presence of one (Ge As) unit besides three (Ge As ) units as a consequence of an exchange reaction in solution was verified by detailed quantum chemical (DFT) calculations, which ruled out all other compositions besides [Au (Ge As)(Ge As ) ] . Reactions of the heavier homologues (Tt Pn ) (Tt=Sn, Pb; Pn=Sb, Bi) did not yield clusters corresponding to that in 1, but dimers of ternary nine-vertex clusters, {[AuTt Pn ] } (in 2-4; Tt/Pn=Sn/Sb, Sn/Bi, Pb/Sb), since the underlying pseudo-tetrahedral units comprising heavier atoms do not tend to undergo the said exchange reactions as readily as (Ge As ) , according to the DFT calculations.
津特耳阴离子（Ge₄As₄）是黄砷的等结构、等电子二元类似物，但迄今为止尚未受到同样强度的研究。将[(PPh₃)AuMe]引入(Ge₄As₄)的1,2 - 二氨基乙烷（en）溶液中，得到异金属簇阴离子[Au₄(Ge₄As₄)(Ge₄As₄)₂]，其盐为[K(crypt - 222)][Au₄(Ge₄As₄)(Ge₄As₄)₂]·en·2 tol（1）。该阴离子是超多面体津特耳簇的罕见例子，并且相对于此类簇中的主族（半）金属原子，它包含的金原子数量最多。整体超四面体结构基于六个金原子构成的（非键合）八面体，该八面体由四个(Ge₄As₄)（x = 2, 3）单元面封端。金原子以矩形方式与四个主族原子结合，以此将四个单元维系在一起形成这种前所未有的结构。通过详细的量子化学（DFT）计算证实，由于溶液中的交换反应，除了三个(Ge₄As₄)单元外还存在一个(Ge₄As)单元，这排除了除[Au₄(Ge₄As₄)(Ge₄As₄)₂]之外的所有其他组成。较重同系物（Tt₄Pn₄）（Tt = Sn, Pb；Pn = Sb, Bi）的反应并未产生与1中对应的簇，而是三元九顶点簇的二聚体{[AuTt₄Pn₄]₂}（在2 - 4中；Tt/Pn = Sn/Sb, Sn/Bi, Pb），因为根据DFT计算，包含较重原子的潜在伪四面体单元不像(Ge₄As₄)那样容易发生上述交换反应。
