Despite established clinical utilisation, there is an increasing need for safer, more inert gadolinium-based contrast agents, and for chelators that react rapidly with radiometals. Here we report the syntheses of a series of chiral DOTA chelators and their corresponding metal complexes and reveal properties that transcend the parent DOTA compound. We incorporated symmetrical chiral substituents around the tetraaza ring, imparting enhanced rigidity to the DOTA cavity, enabling control over the range of stereoisomers of the lanthanide complexes. The Gd chiral DOTA complexes are shown to be orders of magnitude more inert to Gd release than [GdDOTA]−. These compounds also exhibit very-fast water exchange rates in an optimal range for high field imaging. Radiolabeling studies with (Cu-64/Lu-177) also demonstrate faster labelling properties. These chiral DOTA chelators are alternative general platforms for the development of stable, high relaxivity contrast agents, and for radiometal complexes used for imaging and/or therapy.

A versatile π-extension reaction was developed based on the three-component cross-coupling of aryl halides, 2-haloarylcarboxylic acids, and norbornadiene. The transformation is driven by the direction and subsequent decarboxylation of the carboxyl group, while norbornadiene serves as an ortho-C-H activator and ethylene synthon via a retro-Diels-Alder reaction. Comprehensive DFT calculations were performed to account for the catalytic intermediates.

The self-assembly of lanthanide (europium or lanthanium) bimetallic triple helicates from two closely related chiral ligands resulted in a very different supramolecular phenomenon. One gave rise to significantly diastereoselective formation of a triple helicate, whereas the other led to diastereoselective breaking to generate a mixture of P and M diastereomers in ∼1 : 1.1 ratio. The first X-ray crystal structure of a chiral ligand based lanthanide triple-helicate indicates that successive CH-π interactions were found to maintain the supramolecular helical structure.

The coordination of AlCl(3) by the complex [{MeAl(2-py)(3)}Li.thf] () gives the unusual product [{MeAl(2-py)(3)}(2)Al](+)[{MeAl(2-py)(3)}Li](2)(mu-Cl)(-) (), in which the [MeAl(2-py)(3)](-) aluminate anion of acts cooperatively in the coordination of an Al(3+) cation and Cl(-) anion.

Chirality is ubiquitous within biological systems where many of the roles and functions are still undetermined. Given this,there is aclear need to design and develop sensitive chiral optical probes that can function within ab iological setting.Here we report the design and synthesis of magnetically responsive Circularly Polarized Luminescence (CPL) complexes displaying exceptional photophysical properties (quantum yield up to 31 %a nd j g lum j up to 0.240) by introducing chiral substituents onto the macrocyclic scaffolds.M agnetic CPL responses are observed in these chiral Eu III complexes, promoting an exciting development to the field of magnetooptics.The j g lum j of the 5 D 0 ! 7 F 1 transition increases by 20 % from 0.222 (0 T) to 0.266 (1.4 T) displaying al inear relationship between the Dg lum and the magnetic field strength. These Eu III complexes with magnetic CPL responses,p rovides potential development to be used in CPL imaging applications due to improved sensitivity and resolution.

Graceful degradation: The reaction of the [(Me3Si)3Si]− ion with white phosphorus results in a new phosphorus‐based dianion (see scheme; R=Si(SiMe3)3), apparently arising from the unexpected aggregation of two [RP4]− units into a P7 nortricyclic core with an exo anionic P atom. The formation of this dianion sheds new light on the mechanism(s) of P4 degradation by nucleophiles and the ability of silyl substituents to direct product formation.

A bulky and electron-rich N-heterocyclic carbene–palladium complex (SIPr)Ph2 Pd­(cin)Cl was synthesized and characterized. It was found to be highly efficient and versatile for the coupling of different (hetero)­aryl chlorides with various (hetero)­aryl amines at room temperature, especially for the challenging amination of five- or six-membered ring heteroaryl chlorides with five- or six-membered ring heteroaryl amines. It was also successfully applied with high yields to the synthesis of various commercial pharmaceuticals and candidate drugs or compounds with potential pharmacological activities. All of these demonstrate its excellent catalytic efficacy in Buchwald–Hartwig amination and broad application prospects in relevant pharmaceutical preparations. DFT calculations suggest that the steric-induced electronic interaction makes the ligand more electron-donating, and the steric effect effectively regulates the rotation of the iPr-Ph-iPr group in the catalyzed system due to the introduction of the diphenyl skeleton. Considering the electronic effect and the steric effect together, the oxidative addition activation barriers of the (SIPr)Ph2 and (SIPr) ligands are close to each other. Reductive elimination is the rate-determining step of the (SIPr)Ph2 Pd­(cin)­Cl-catalyzed system in the catalytic cycle, and the appropriate steric hindrance of the (SIPr)Ph2 ligand greatly reduces the energy barrier of this step. The perfect combination of the electron-donating and steric hindrance abilities of the ligand significantly improves the catalytic activity.

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