Incorporation of CuO NPs into modified UiO-66-NH₂ metal-organic frameworks (MOFs) with melamine for catalytic C-O coupling in the Ullmann condensation

TY - JOUR

T1 - Incorporation of CuO NPs into modified UiO-66-NH2 metal-organic frameworks (MOFs) with melamine for catalytic C-O coupling in the Ullmann condensation

AU - Sadeghi, Samira

AU - Jafarzadeh, Mohammad

AU - Abbasi, Amir Reza

AU - Daasbjerg, Kim

PY - 2017/10/21

Y1 - 2017/10/21

N2 - Herein, the UiO-66-NH 2 metal-organic framework (MOF) is initially modified with melamine via a post-synthetic approach. CuO nanoparticles (NPs) are then anchored via the available functional groups (amine groups and π-electron interactions of melamine and ligand) on the surface of the modified MOF. The as-synthesized UiO-66-NH 2-Mlm/CuO NPs are characterized using different techniques including XRD, TGA, TEM, EDX, and XPS. The CuO-supported MOF is successfully used as a heterogeneous catalyst for C-O coupling in Ullmann condensation. A catalytic amount of the supported catalyst (5% CuO) promotes the condensation reaction for various aryl chlorides, bromides, and iodides under mild reaction conditions (100 °C with KOH serving as a base) in good yield (30-95%) within 18-24 h. Even in the absence of KOH, the reaction is enabled with 55% yield in 24 h by grafting melamine with amine groups to create base active sites on the MOF, which indicates the additional role of the support as a base active site. The supported catalyst is easily recycled and reused several times with negligible loss in its activity. Furthermore, the copper leaching from the catalyst is as low as 1.2 wt% after being reused four times.

AB - Herein, the UiO-66-NH 2 metal-organic framework (MOF) is initially modified with melamine via a post-synthetic approach. CuO nanoparticles (NPs) are then anchored via the available functional groups (amine groups and π-electron interactions of melamine and ligand) on the surface of the modified MOF. The as-synthesized UiO-66-NH 2-Mlm/CuO NPs are characterized using different techniques including XRD, TGA, TEM, EDX, and XPS. The CuO-supported MOF is successfully used as a heterogeneous catalyst for C-O coupling in Ullmann condensation. A catalytic amount of the supported catalyst (5% CuO) promotes the condensation reaction for various aryl chlorides, bromides, and iodides under mild reaction conditions (100 °C with KOH serving as a base) in good yield (30-95%) within 18-24 h. Even in the absence of KOH, the reaction is enabled with 55% yield in 24 h by grafting melamine with amine groups to create base active sites on the MOF, which indicates the additional role of the support as a base active site. The supported catalyst is easily recycled and reused several times with negligible loss in its activity. Furthermore, the copper leaching from the catalyst is as low as 1.2 wt% after being reused four times.

KW - EFFICIENT HETEROGENEOUS CATALYST

KW - REUSABLE CATALYST

KW - CU2O NANOPARTICLES

KW - FACILE SYNTHESIS

KW - COPPER CATALYST

KW - BOND FORMATION

KW - ARYL HALIDES

KW - ALCOHOLS

KW - DERIVATIVES

KW - OXIDATION

UR - http://www.scopus.com/inward/record.url?scp=85031044038&partnerID=8YFLogxK

U2 - 10.1039/c7nj02114c

DO - 10.1039/c7nj02114c

M3 - Journal article

SN - 1144-0546

VL - 41

SP - 12014

EP - 12027

JO - New Journal of Chemistry

JF - New Journal of Chemistry

IS - 20

ER -