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An open‐cage fullerene incorporating phosphorous ylid and carbonyl group moieties on the rim of the orifice can be filled with gases (H2, He, Ne) in the solid state, and the cage opening then contracted in situ by raising the temperature to complete an intramolecular Wittig reaction, trapping the atom or molecule inside. Known transformations complete conversion of the product fullerene to C60 containing the endohedral species. As well as providing an improved synthesis of large quantities of 4He@C60, H2@C60, and D2@C60, the method allows the efficient incorporation of expensive gases such as HD and 3He, to prepare HD@C60 and 3He@C60. The method also enables the first synthesis of Ne@C60 by molecular surgery, and its characterization by crystallography and 13C NMR spectroscopy. [ABSTRACT FROM AUTHOR]

An open‐cage fullerene incorporating phosphorous ylid and carbonyl group moieties on the rim of the orifice can be filled with gases (H2, He, Ne) in the solid state, and the cage opening then contracted in situ by raising the temperature to complete an intramolecular Wittig reaction, trapping the atom or molecule inside. Known transformations complete conversion of the product fullerene to C60 containing the endohedral species. As well as providing an improved synthesis of large quantities of 4He@C60, H2@C60, and D2@C60, the method allows the efficient incorporation of expensive gases such as HD and 3He, to prepare HD@C60 and 3He@C60. The method also enables the first synthesis of Ne@C60 by molecular surgery, and its characterization by crystallography and 13C NMR spectroscopy. [ABSTRACT FROM AUTHOR]

The highly strained cubane system is of great interest as a scaffold and rigid linker in both pharmaceutical and materials chemistry. A straightforward approach is reported for the scale-up of a [2+2] photocycloaddition step using convenient home-made flow photoreactors to access dimethyl 1,4-cubanedicarboxylate on decagram-scale in 33–40% yield over 8 steps. The process is demonstrated on 3.4 g·h–1 input with 30 minutes residence time, enabling to reduce the process time and to avoid the use of batch photoreactors. Completion of the characterisation of the photocycloadduct and its hydrates is reported. [ABSTRACT FROM AUTHOR]

Abstract Background The crystal structure of 2,2-trimethylenedioxy-4,4,6,6-tetrachlorocyclo triphosphazene has been determined at 120, 274 and 293 K. The result at 293 K confirms the room temperature Cmc21 structure, but at the lower temperatures the space group is Pna21. Nevertheless the basic structure remains the same, with only small displacements of the atoms, amounting to an average of 25 pm between 120 and 293 K. Results X-ray diffraction and DSC results indicate that the phase transition takes place in two steps between 274 – 293 K and provides an understanding of previous NQR results. In the intermediate temperature range the molecules are displaced from their room temperature positions in such a way as to give an average structure with Cmc21 symmetry. Conclusion The overall phase transition is consistent with the occurrence of a soft lattice mode at room temperature in which a large displacement of the molecule in the x-direction is coupled with a flexing motion about an axis defined by the nitrogen atoms in the N1 and N3 positions.

Research has been conducted on the CH (sub)2 Cl (sub)2. The crystal structure and the physical properties of this compound have been investigated and the results indicate that the CH (sub)2 Cl (sub)2 solvate exhibits the donor layer disorder.

A new Bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) charge-transfer salt containing the novel anion [Fe(sub 2)(C(sub 2)O(sub 4))(sub 5)](super 4-) is presented. An antiferromagnetic interaction between pairs of FE atoms results from the bridging oxalate ligand providing an exchange pathway between the two Fe(super III) centers.

The highly strained cubane system is of great interest as a scaffold and rigid linker in both pharmaceutical and materials chemistry. The first electrochemical functionalisation of cubane by oxidative decarboxylative ether formation (Hofer–Moest reaction) was demonstrated. The mild conditions are compatible with the presence of other oxidisable functional groups, and the use of flow electrochemical conditions allows straightforward upscaling. [ABSTRACT FROM AUTHOR]

An intramolecular [S.sub.N]Ar mechanism is identified in the unexpected aryl migration observed in a mesomeric betaine. The process has changed the optical and spectroscopic properties and it is a valuable model for related heteroaromatic systems.

Thionyl chloride (SO[Cl.sub.2]) has acted as halogenation reagent in its reaction with 1-[phenyl(hydroxy)methyl]-2-R-1,2-dicarba-closo-dodecaborane, but has unexpectedly behaved as an oxidant for 1-[2'-pyridyl(hydroxy)methyl]-2-R-1,2-dicarba-closo-dodecaboranes. The synthesis and characterization of all the new compounds are discussed.

A series of 2,7-functionalized indoles are synthesized with appended amide and urea or thiourea groups. Anion complexation studies have indicated a difference in the mode of interaction of carboxylates with indole-ureas vs indole-amides.

The preorganization of a structurally simple receptor with intramolecular hydrogen bonds has increased both the affinity and selectivity of anion binding. The 4,6-dihydroxyisophthalamide is found to be a potent transmembrane [Cl.sup.-] transporter, which can be controlled by pH.