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A family of p-cyclophanes based on bis- or tetrafunctionalized 1,4-bisthiophenol units linked by disulfide bridges was obtained by self-assembly on a gram scale and without any chromatographic purification. The nature of the functionalities borne by these so-called dyn[4]arenes plays a crucial role on their structural features as well as their molecular recognition abilities. Tuning these functions on demand yields tailored receptors for cations, anions, or zwitterions in organic or aqueous media.

1H, (19)F and (31)P pulsed field gradient spin-echo (PGSE) diffusion studies on chiral organic salts that contain hexacoordinate phosphate anions, namely tris(tetrachlorobenzenediolato)phosphate(V) (TRISPHAT) and bis(tetrachlorobenzenediolato)mono([1,1']binaphthalenyl-2,2'diolato)-phosphate(V) (BINPHAT), are reported. The first example of the dependence of a diffusion value on diastereomeric structure is presented. Marked solvent and concentration effects on the diffusion constants (D) of these salts are noted and the question of ion pairing is discussed.

A new method of synthesis of homo- and heteroleptic cis bis-chelated Pd(II) species by a transmetalation reaction of the ortho-mercurated 2-[tricarbonyl(η6-phenyl)chromium]pyridine with a series of bis(μ-chloro) palladacyclic aromatic compounds in the presence of a large excess of the chloride salt [NMe4]Cl is reported. These (CO)3Cr-bound bis-chelated Pd(II) species can be designed for the preparation of enantiopure planar chiral cyclopalladated (η6-arene)Cr(CO)3 complexes. The study of the mechanism of this transmetalation reaction reveals the key role of the excess of chloride salt, which is necessary for the isolation of persistent heteroleptic bis-chelated Pd(II) complexes. This method was further applied to the synthesis of highly enantioenriched (+) and (−) samples of the ortho-chloropalladated 2-[tricarbonyl(η6-phenyl)chromium]pyridine, whose enantiopurity was assessed with the aid of diamagnetic Λ and Δ TRISPHAT salts used as chiral shift 1H NMR agents. The absolute configurations of the two enantioenriched complexes were obtained from the corresponding absolute structures determined by X-ray diffraction analyses. The molecular structures of six new heteroleptic bis-chelated Pd(II) complexes are reported.

Despite the growing use of poly-l-lysine dendrigrafts in biomedical applications, a deeper understanding of the molecular level properties of these macromolecules is missing. Herein, we report a simple methodology for the construction of three-dimensional structures of poly-l-lysine dendrigrafts and the subsequent investigation of their structural features using microsecond molecular dynamics simulations. This methodology relies on the encoding of the polymers' experimental characterizations (i.e., composition, degrees of polymerization, branching ratios, charges) into alphanumeric strings that are readable by the Amber simulation package. Such an original approach opens avenues toward the in silico exploration of dendrigrafts and hyperbranched polymers.

[formula: see text] Stereodynamics were detected in solution for salts of the simple spirobi[dibenzazepinium] cation in favor of the homochiral (D2) conformer as evidenced by chiral TRISPHAT and BINPHAT counterions; asymmetric induction was furthermore observed in 1H and 15N NMR spectroscopy.