A new isoreticular series of metal–organic frameworks, called UHM-25 (UHM: University of Hamburg Materials), based on the copper paddle wheel motif and a novel set of homochiral linkers has been synthesized. Starting from amino acids available from the chiral pool a synthesis procedure was established that allows a straightforward, multigram scale synthesis of homochiral linkers in 4–5 steps. These linkers carry substituents that have been proven useful in stereoselective organic chemistry, such as the Evans auxiliary or chiral amino alcohols. The resulting MOFs only differ in the chiral moiety provided by the amino acid starting material. The structure of UHM-25 is composed of cuboctahedral cages of Cu2 paddle wheel motifs connected by the isophthalate moieties of the linker. These cages are linked via the bent backbone of the linker resulting in a primitive cubic arrangement, giving rise to the rare underlying (3,4)-c binodal net ucp. MOFs of the UHM-25 series show surface areas up to S BET = 1900 m2/g. Postsynthetic modification reactions with excellent conversion rates confirmed the accessibility to the chiral groups. Furthermore, UHM-25-Pro bearing a prolinol functionality was used in a self-directed, enantioselective aldol addition of acetaldehyde, demonstrating the potential of the UHM-25 series with regard to heterogeneous, stereoselective catalysis.

The cationic homo-and heteronuclear sandwich complexes (η 5 -cyclopentadienyl)(ferrocenylethynyl-η 6 -benzene)ruthenium(II) hexafluoridophosphate (3a), (η 5 -cyclopentadienyl)-(ruthenocenylethynyl-η 6 -benzene)ruthenium(II) hexafluoridophosphate (3b), (η 5 -cyclopentadienyl)[1,4-bis(ferrocenylethynyl)η 6 -benzene]ruthenium(II) hexafluoridophosphate (4a), (η 5cyclopentadienyl)[1,4-bis(ruthenocenylethynyl)-η 6 -benzene]ruthenium(II) hexafluoridophosphate (4b), and (η 5cyclopentadienyl)[1,3,5-tris(ferrocenylethynyl)-η 6 -benzene]ruthenium(II) hexafluoridophosphate (5) were synthesized by means of Stille cross-coupling reaction using tri-n-butyl-(metallocenylethynyl)stannane as nucleophile and the appropriate (η 5 -cyclopentadienyl)(η 6 -iodobenzene)ruthenium(II) cations as electrophiles. As a catalyst, a Pd(0) complex, furnished with AsPh 3 ligands, was applied. The hitherto unknown iodobenzene complexes (η 5 -cyclopentadienyl)(1,4-η 6 -diiodobenzene)ruthenium(II) hexafluoridophosphate (1b) and (η 5 -cyclopentadienyl)(η 6 -1,3,5-triiodobenzene)ruthenium(II) hexafluoridophosphate (1c) as well as the described cationic homo-and heteronuclear sandwich complexes 3−5 were fully characterized and investigated with respect to the second-harmonic generation by hyper-Rayleigh scattering. For complexes 1b, 1c, 3a, and 5 X-ray structure determinations were performed.

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The isostructural 1-bromo and 1-iodo derivatives of 3,5-bis­(1,3-oxazolin-2-yl)benzene show supra­molecular features of (non-classical) hydrogen bonding, parallel-displaced π–π inter­actions, and close N⋯I contacts. The former was found to crystallize as a sub-hydrate.

Four metal–organic frameworks employing the m-terphenyl diisophthalate linker molecule with 2′ substitution by P(v)-based functional groups of the central aryl have been synthesised.