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Developing efficient, robust, and highly recyclable catalysts with the ability to separate products conveniently for industrially important hydrogenation reactions is a major challenge. Edges of nanoparticles possessing selective catalytic properties while the completely exposed metal particles are devoid of this attribute is a known fact. Herein, the preparation and evaluation of a Co 3 O 4 /N-Gr/Fe 3 O 4 magnetic heterostructure composed of Co 3 O 4 nanoparticles surrounded by nitrogen-doped graphitic carbon derived from ZIF-67 on an Fe 3 O 4 support is described. Wrapping Co 3 O 4 nanoparticles with porous nitrogen-rich graphitic carbon increases their catalytic selectivity and durability. Co 3 O 4 /N-Gr/Fe 3 O 4 is obtained by pyrolysis of metal−organic frameworks, ZIF-67(Co) with magnetic Fe 3 O 4 nanoparticles under nitrogen. Scanning electron microscopy reveals Fe 3 O 4 as uniform octagonal microcrystals (∼450 nm) and transmission electron microscopy (TEM) shows graphitic carbon layers around the core Co 3 O 4 nanoparticles on Fe 3 O 4 microcrystals. TEM using a high-angle annular dark-field with spherical aberration (Cs) correction shows the core−shell structure of Co 3 O 4 /N-Gr nanocrystals (∼20 nm) with the graphitic carbon layers surrounding the core Co 3 O 4 nanoparticles on Fe 3 O 4 microcrystals. The resulting Co 3 O 4 /N-Gr/Fe 3 O 4 construct produces a stable and reusable catalyst for the selective hydrogenation of structurally diverse N-heteroarenes. Particularly, quinoline was quantitatively hydrogenated to 1,2,3,4-tetrahydroquinoline (py-THQ) at 120 °C under 40 bar of H 2 . The wide applicability of Co 3 O 4 /N-Gr/Fe 3 O 4 was tested for selective hydrogenation of cinnamaldehyde to hydrocinnamaldehyde (HCAL) with >99% selectivity. Also, the tolerance of functional groups in the reduction of nitroarene was evaluated. The benefit of the ability to produce py-THQ was demonstrated by extending the protocol for the synthesis of bioactive molecules, that is, a tubulin polymerization inhibitor with a 94% yield. The robust nature of the Co 3 O 4 /N-Gr/ Fe 3 O 4 construct was demonstrated through multiple cycles of simple separation and reuse.

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A cost-effective aluminum CHA zeolite was synthesized by seed-assisted hydrothermal synthesis under microwave radiation to shorten the crystallization time to 6 h. The CHA was synthesized under different stirring rates and evaluated in methanol-to-olefins reaction at three different temperatures by using a fixed-bed reactor. Boron was incorporated by in situ synthesis also under microwave radiation. The X-ray diffraction pattern revealed that the synthesized CHA was crystalline and in well agreement with the reference CHA. The reaction evaluation revealed that the reaction temperature affected both the catalyst stability and selectivity to light olefins. At a lower temperature, the synthesized CHA was more stable and less selective to olefins, while at a higher temperature, the catalyst was less stable and more selective to olefins. The incorporation of boron only enhanced the selectivity to ethylene and propylene at the start of the reaction.