Hydroamination of Phenylacetylene with Aniline over Gold Nanoparticles Embedded in the Boron Imidazolate Framework BIF-66 and Zeolitic Imidazolate Framework ZIF-67

Abstract

The hydroamination of alkynes is an atom-economy process in the organic synthesis for the C–N bond formation, thereby allowing the production of fine chemicals and intermediates. However, direct interaction between alkynes and amines is complicated due to the electron enrichment of both compounds. Therefore, efficient hydroamination catalysts, especially heterogeneous ones, are in great demand. This work aimed at the development of novel heterogeneous catalysts based on zeolite-like metal–organic frameworks for phenylacetylene hydroamination. The sodalite (SOD) type zeolitic imidazolate framework ZIF-67 (Co­(meim)2, meim = 2-methylimidazolate) and boron imidazolate framework BIF-66 ({Co­[B­(im)4]2}n, im = imidazolate) were studied as the carriers for the gold nanoparticles (Au-NPs). Au-NPs were embedded in the ZIF-67 and BIF-66 matrices by incipient wetness impregnation. Au@ZIF-67 and Au@BIF-66 hybrids were studied for the first time in the liquid phase hydroamination of phenylacetylene with aniline in an air atmosphere and have shown high activity and selectivity in respect to imine in this process. The pronounced impact of the nature of the metal–organic carrier, Au source, and reducing agent on the catalytic performance of the synthesized nanomaterials was found. To the best of our knowledge, it is the first example of using the zeolitic imidazolate framework and boron-imidazolate framework as the components of the gold-containing catalytic systems for the alkyne hydroamination.

Dynamic behavior of metal nanoparticles in MOF materials: analysis with electron microscopy and deep learning

“…MOFs were synthesized according to published procedures. [76][77][78][79][80][81][82] The MIL-101(Fe) and NH 2 -MIL-101(Fe) samples were prepared by the MW technique under atmospheric pressure according to a modified previously reported procedure. 78 For the synthesis of MIL-101(Fe), benzene-1,4-dicarboxylic acid (H 2 BDC) (0.230 g, 1.38 mmol) was dissolved in N, N-dimethylformamide (DMF) (60 mL).…”

Boron-imidazolate coordination networks with 3d transition metals for enhanced CO2 adsorption capability

“…Boron-bridged ligands can form three-dimensional structures with various metal ions. To date, several types of BIFs have been synthesised from boron-bridged ligands and various metal ions such as Li, 4,7,8 Co, [9][10][11][12][13][14] Cu, [15][16][17][18][19][20][21][22] Zn, [23][24][25][26][27][28][29][30][31] Ru, 32 and Cd ions. [33][34][35][36][37][38][39] In this study, we focus on BIF-3-Cu as a typical example, which consists of Cu + ions and [B(2-methylimidazolate) 4 ] À ([B(2-MIm) 4 ] À ).…”

“…Boron-bridged ligands can form three-dimensional structures with various metal ions. To date, several types of BIFs have been synthesised from boron-bridged ligands and various metal ions such as Li, 4,7,8 Co, 9–14 Cu, 15–22 Zn, 23–31 Ru, 32 and Cd ions. 33–39…”