Synergistic catalysis: Highly enantioselective acetyl aza-arene addition to enals

A novel catalytic enantioselective methodology based on synergistic catalysis for the synthesis of chiral 2‐acyl pyridines and pyrazines is reported. The strategy involves the metal–Lewis acid activation of acetyl aza‐arenes and the secondary‐amine activation of enals. The proposed mechanism is supported by DFT calculations

Characterisation of the confining potential for He atoms in the endofullerenes 3He@C60 and 4He@C60 by INS over an extended energy range

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Probing the interaction of noble gases with the inside of a C60 carbon cage, INS of 3He@C60 and Ne@C60 endofullerene

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Quantised translational states of atomic He confined inside a nearly spherical cage: the endofullerene He@C60

Highly innovative &#39;molecular surgery&#39; techniques have been developed in recent years to synthesise small molecule endofullerenes in which the molecular cage of C60 completely encloses and entraps a quantum rotor such as H2, H2O or HF. The physical entrapment provides a nanolaboratory environment in which to study the isolated molecule and to exploit its physical properties. In this new proposal we are shifting emphasis to the study of entrapped atomic species. In particular 3He is highly receptive to NMR with the capacity to be prepared in a hyperpolarised nuclear spin state. Yet to develop laser-pumping hyperpolarisation protocols and exploit the possibilities that such a spin system far from equilibrium would provide, a detailed characterisation of the translational energy levels of the He atom inside its cage is required. This is uniquely available using neutron scattering.</span

First synthesis and characterization of CH4@C60

The endohedral fullerene CH4@C60, in which each C60 fullerene cage encapsulates a single methane molecule, has been synthesised for the first time. CH4 is the largest molecule, with the greatest number of atoms, to have been encapsulated in C60 to date. The key orifice contraction step, a photochemical desulfinylation of an open fullerene, was successfully completed, even though it is significantly inhibited by the presence of the endohedral molecule. The 13C NMR resonance for the cage nuclei in CH4@C60 is deshielded by Dd = +0.52 ppm relative to C60. The crystal structure of the nickel(II) octaethylporphyrin / benzene solvate shows no significant distortion of the carbon cage, relative to the C60 analogue, and shows the methane hydrogens as a shell of electron density around the central carbon, indicative of the quantum nature of the methane, existing in a set of quantised rotational-translational states at 100 K. The 1H and 13C spin-lattice relaxation times (T1) for endohedral methane havebeen measured. The 1H T1 values are similar to those observed in the gas phase, also indicating that methane is freely rotating inside the C60 cage. The 1H relaxation rate constant T1 -1 increases with increasing temperature and suggests a significant spin-rotation contribution to the relaxation. The successful synthesis of CH4@C60 opens a route to endofullerenes incorporating larger guest molecules than those encapsulated previously

First Synthesis and Characterisation of CH4@C60

Raw data supporting journal article: Bloodworth, S. et al (2019). First Synthesis and Characterisation of CH4@C60. Angewandte Chemie International Edition. DOI: 10.1002/anie.201900983 and 10.1002/ange.201900983 </span