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A new tetrahedral coordination cage M12L6 was prepared from a linear dipyrimidine ligand (L) and cis-protected palladium(II) (M). This cage showed unprecedented host-guest chemistry where the cationic host accommodated a cationic guest despite 24+ charges on the host framework. The unusual cation-cation host-guest chemistry is described by a unique onionlike shell structure of the host-guest complex where two cationic spheres are mediated by an anionic sphere of a counteranion assembly.

An unprecedented addition pattern for the novel hexakis‐cyclopropanated C60 (±)‐1 was prepared by a sequence of tether‐directed regioselective remote functionalizations. The X‐ray crystal structure revealed the positioning of the six addends in a distinct helical array along an equatorial belt.

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Representatives of two classes of hexakis-adducts of C 60 were prepared by templated synthesis strategies. Compound 8 with a dipyridylmethano addend in a pseudo-octahedral addition pattern was obtained by DMAtemplated addition (DMA 9,10-dimethylanthracene; Scheme 1) and served as the starting material for the first supramolecular fullerene dimer 2. Hexakis-adduct 12 also possesses a pseudo-octahedral addition pattern and was obtained by a sequence of tether-directed remote functionalization, tether removal, and regioselective bis-functionalization (Scheme 2). With its two diethynylmethano addends in trans-1 position, it is a precursor for fascinating new oligomers and polymers that feature C 60 moieties as part of the polymeric backbone ( Fig. 1).With the residual fullerene p-electron chromophore reduced to a cubic cyclophane-type sub-structure (Fig. 4), and for steric reasons, 8 and 12 no longer display electrophilic reactivity. As a representative of the second class of hexakis-adducts, (AE)-1, which features six addends in a distinct helical array along an equatorial belt, was prepared by a route that involved two sequential tether-directed remote functionalization steps (Schemes 3 and 5). In compound (AE)-1, p-electron conjugation between the two unsubstituted poles of the carbon sphere is maintained via two (E)-stilbene-like bridges (Fig. 4). As a result, (AE)-1 features very different chemical reactivity and physical properties when compared to hexakis-adducts with a pseudo-octahedral addition pattern. Its reduction under cyclic voltammetric conditions is greatly facilitated (by 570 mV), and it readily undergoes additional, electronically favored Bingel additions at the two sterically well-accessible central polar 6-6 bonds under formation of heptakis-and octakis-adducts, (AE)-30 and (AE)-31, respectively (Scheme 6). The different extent of the residual p-electron delocalization in the fullerene sphere is also reflected in the optical properties of the two types of hexakis-adducts. Whereas 8 and 12 are bright-yellow (end-absorption around 450 nm), compound (AE)-1 is shiny-red, with an end-absorption around 600 nm. This study once more demonstrates the power of templated functionalization strategies in fullerene chemistry, providing addition patterns that are not accessible by stepwise synthetic approaches.1. Introduction. ± Among the higher adducts of buckminsterfullerene (C 60 ; for a recent example, see [1]), hexakis-adducts are increasingly attracting interest as threedimensional scaffolds for advanced materials applications [2] [3]. Among those, derivatives with a pseudo-octahedral (T h ) addition pattern have been the earliest and most widely investigated ones [4 ± 8]. Also known is a hexakis-adduct with a D 3 -symmetrical addition pattern [2]. Both types of hexakis-adducts are accessible by stepwise additions, and their addends are evenly distributed over the entire carbon sphere. In this paper, we describe the synthesis of new hexakis-adducts with the T hsymmetrical addition pattern, which are useful...

Die regioselektive Bingel‐Makrocyclisierung der C60‐Kohlenstoffkugel mit einem Bismalonat, das einen Dibenzo[18]krone‐6‐Spacer enthält, eröffnet erstmals einen allgemeinen Zugang zu trans‐1‐Fulleren‐Bisaddukten wie (±)‐1. Die Komplexierung von Kaliumionen durch (±)‐1 hat einen starken Einfluß auf die Redoxeigenschaften des Fullerens infolge der engen räumlichen Nähe zwischen der Fullerenoberfläche und dem kronenethergebundenen Kation, die sich aus der doppelten Verbrückung ergibt.

Poly(lactic acid) (PLA) is a promising biodegradable polymer based on renewable resources. This paper describes scale-up studies to synthesize high molecular weight PLA (>100'000 g/mol) in five steps from commercial lactic acid. The first four steps of this process consist of synthesizing a highly pure precursor, lactide, which can be converted into a high molecular PLA by ring opening polymerization (ROP). We produced PLA with a molecular weight of 109'000 g/mol using this strategy.

The low-density lipoprotein (LDL)-mimetic lipid nanoparticles (LNPs), decorated with MRI contrast agents, and fluorescent dyes, were prepared by the covalent attachment of apolipoprotin-mietic peptide (P), Gd(III)-chelate (Gd), and sulforhodamine B...