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Die Enthalogenierung von Alkylantimondibromiden RSbBr2 (R = Et, Pr, Bu) mit Mg in THF führt zu gelben Lösungen, die überwiegend die Antimonfünfringe (RSb)5 neben den Vierringen (RSb)4 enthalten. Die Trimeren (RSb)3 können massenspektrometrisch nachgewiesen werden. Beim Entfernen des Lösungsmittels bilden sich reversibel die Polymeren (RSb)x (x » 5) in Form schwarzer Festkörper. In den Ringen nehmen die Substituenten R maximale trans‐Positionen ein. Die Kristallstruktur von (MesSb)4 · Benzol enthält linear …Sb4…Sb4…‐verknüpfte Cyclotetrastiban‐Aren‐Komplexe mit guter η6‐Haptizität des Benzolmoleküls an eines der vier Sb‐Atome (Ringmitte…Sb 3.81 Å, Winkel zur Flächennormale 5°). Der Sb4‐Ring ist stark und uneinheitlich gefaltet.

Tetrazine mediated inverse Electron Demand Diels–Alder Reaction (IEDDA) is an important modification technique due to its high selectivity and super‐fast kinetics. Incorporation of tetrazine moieties on polymer chains requires multistep synthetic pathways and a post‐polymerization step leading to functional polymeric materials. Such approaches involve separate syntheses of polymer and the molecule which will be employed in modification. Herein, we introduce a straightforward synthetic approach for direct synthesis of tetrazine groups on polymers as side chains. As model systems, tetrazine functional poly(N‐isopropylacrylamide)‐and poly(ethylene glycol)‐based polymers from corresponding precursor polymers with nitrile moieties as pendant groups are prepared and IEDDA Click Reaction is achieved with trans‐cyclooctene derivatives. The click reaction is monitored by both NMR and UV–vis spectroscopies. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 673–680

Trimesitylstibane (1) reacts with SbCl3 or SbBr3 to form the halostibanes Mes2SbCl (2), MesSbCl3 (3), Mes2SbBr (4). or MesSbBr2 (5) [Mes = 2,4,6-(CH3)3C6H2]. Action of MesMgCl on an excess of SbCl3 or SbBr3 at low temperatures gives Mes3SbCl2 (6) or Mes3SbBr2 (7), resp. Addi­tion of Br2 to 1 gives 7 in 96% yield. The silylstibanes Mes2SbSiMe3 (8) and McsSb(SiMc3)2 (9) are formed by dehalogenation of Me3SiCl and 4 or 5 by Mg filings in tetrahydrofuran. Mes2SbOSiMe3 (10) is obtained by air oxidation of 8. Reduction of 4 with Mg gives Mes2SbSbMes2 (19). Crystals of the composition (MesSb)6·C6H6 (13a) or (MesSb)4·C6H5CH3 (13b) are obtained from Mg and 5 after work-up in benzene or toluene, resp.

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