Zirconium Metal–Organic Frameworks Assembled from Pd and Pt P^NN^NP Pincer Complexes: Synthesis, Postsynthetic Modification, and Lewis Acid Catalysis

Abstract

Carboxylic acid-functionalized Pd and Pt PNP pincer complexes were used for the assembly of two porous Zr metal-organic frameworks (MOFs), 2-PdX and 2-PtX. Powder X-ray diffraction analysis shows that the new MOFs adopt cubic framework structures similar to the previously reported ZrO(OH)[(PCP)PdX], [PCP = 2,6-(OPAr)CH); Ar = p-CHCO, X = Cl, I] (1-PdX). Elemental analysis and spectroscopic characterization indicate the presence of missing linker defects, and 2-PdX and 2-PtX were formulated as ZrO(OH)(OAc)[M(PNP)X] [M = Pd, Pt; PNP = 2,6-(HNPAr)CHN; Ar = p-CHCO; X = Cl, I]. Postsynthetic halide ligand exchange reactions were carried out by treating 2-PdX with Ag(OSCF) or NaI followed by PhI(OCCF). The latter strategy proved to be more effective at activating the MOF for the catalytic intramolecular hydroamination of an o-substituted alkynyl aniline, underscoring the advantage of using halide exchange reagents that produce soluble byproducts.

Immobilization of an Iridium Pincer Complex in a Microporous Polymer for Application in Room‐Temperature Gas Phase Catalysis

“…Organometallic pincer complexes have received tremendous attention due to their great number of applications in homogeneous catalysis, such as dehydrogenation, coupling, hydrogen transfer, as well as aldol and Michael reactions. [1][2][3][4][5][6][7][8][9] Immobilization of pincer complexes by covalent bond formation with the supporting material, such as silica and metal oxides [10][11][12][13][14][15][16][17][18] as well as metal-organic frameworks [19][20][21][22][23] have been reported. Immobilization of molecular catalysts onto porous materials combines advantages of homogeneous as well as heterogeneous catalysis, such as high conversion rates and good reusability.…”

Immobilization of an Iridium Pincer Complex in a Microporous Polymer for Application in Room‐Temperature Gas Phase Catalysis

“…Immobilization of pincer complexes by covalent bond formation with the supporting material, such as silica and metal oxides [10–18] as well as metal‐organic frameworks [19–23] have been reported. Immobilization of molecular catalysts onto porous materials combines advantages of homogeneous as well as heterogeneous catalysis, such as high conversion rates and good reusability [24, 25] .…”

Metal–Organic Frameworks Based on Group 3 and 4 Metals

“…Zhou and co-workers also reported a series of tetratopic ligands with different symmetries and Zr-MOFs with flu (PCN-605 or UMCM-312), scu (PCN-606), and csq (PCN-608) topologies were formed. [206][207][208] In past two years, lots of Zr-MOFs with the abovementioned topologies have been documented, including ftw (Zr-bptc, [209] Zr-IAM-4, [210] and Zr-PdX [211] ), csq (BUT-17, [212] MIP-200, [213] and NU-100x, x = 3, 4, 5, 6, 7, [214] 8 [215] ), scu (Zr-TTFTB, [216] PCN-901-SO 2 , [217,218] LIFM-114, [219] BUT-62, [220] BUT-63, [220] BUT-74, [221] Zr-abtc, [209] Zr-LMOF [222] and UU-100 [223] ), she (Zr-Me-TTFTB [216] ), sqc (MFM-601 [224] or BUT-15, [225] BUT-72, [221] and BUT-73 [221] ), and flu (PCN-902-O [217] ). The spirobifluorenelinkerbased ftw MOF Zr-IAM-4 is a twofold interpenetrated s tructure, which is different from PCN-221.…”