No abstract

trans-1,2-Diaminocyclohexane functionalized mesoporous silica was applied as an ideal catalyst for asymmetric Michael addition of various nitroalkane derivatives. Short channels and plugs in the pore structure offered chiral enhancement in Michael addition.

Amine functionalized disk type mesoporous silica was directly synthesized by co-condensation method for the encapsulation of hexahydro-1,3,5-trinitro-s-triazine (RDX), aiming for the desensitization of such high energetic material. The adsorption capacities were measured by TG analysis and pore-filling adsorption efficiencies of RDX were estimated based on sorption amounts with respect to pore volume of amino-functionalized mesoporous silica. The RDX was encapsulated as nanoparticles in the (NH2)-INC-2 due to the confinement effect within the size of mesopores and shows adsorption efficiency upto 80% at with respect to pore-filling. The confinement effect is also depicted by lowering of the T(rho) (190 degrees C) when encapsulated compared with that of free RDX. The non-neutralized amino-functionalized (cationic (NH3+)-INC-2) gave more 80% adsorption efficiency at 25% loading and the T(rho) were comparatively higher due to the ionic interaction between RDX and quaternary amine group.

Space by the Plug Effect. -Highly enantioselective addition of α,β-unsaturated ketones to nitroalkenes is achieved at ambient temperature in the presence of a protonic acid and trans-1,2-diaminocyclohexane functionalized mesoporous silica as catalyst. Short channel and plugs in the pore structure offer a significant enhancement of enantioselectivity in the Michael addition. -(JEONG, E.-Y.; LIM, C.-R.; JIN, H.; PARK*, S.-E.; Chem. Commun. (Cambridge) 48 (2012) 25, 3079-3081, http://dx.