Zirconium Metal-Organic Frameworks Assembled from Pd and Pt PNNNP Pincer Complexes: Synthesis, Postsynthetic Modification, and Lewis Acid Catalysis

Benjamin R Reiner; Neil T Mucha; Anna Rothstein; J Sebastian Temme; Pu Duan; Klaus Schmidt-Rohr; Bruce M Foxman; Casey R Wade

doi:10.1021/acs.inorgchem.7b03063

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

Inorg Chem. 2018 Mar 5;57(5):2663-2672. doi: 10.1021/acs.inorgchem.7b03063. Epub 2018 Feb 13.

Authors

Benjamin R Reiner, Neil T Mucha, Anna Rothstein, J Sebastian Temme, Pu Duan, Klaus Schmidt-Rohr, Bruce M Foxman, Casey R Wade¹

Affiliation

¹ Department of Chemistry , Brandeis University , 415 South Street MS 015 , Waltham , Massachusetts 02453 , United States.

PMID: 29437384
DOI: 10.1021/acs.inorgchem.7b03063

Abstract

Carboxylic acid-functionalized Pd and Pt P^NN^NP 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 Zr₆O₄(OH)₄[(P^OC^OP)PdX]₃, [P^OC^OP = 2,6-(OPAr₂)₂C₆H₃); Ar = p-C₆H₄CO₂^-, 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 Zr₆O₄(OH)₄(OAc)_2.4[M(P^NN^NP)X]_2.4 [M = Pd, Pt; P^NN^NP = 2,6-(HNPAr₂)₂C₅H₃N; Ar = p-C₆H₄CO₂^-; X = Cl^-, I^-]. Postsynthetic halide ligand exchange reactions were carried out by treating 2-PdX with Ag(O₃SCF₃) or NaI followed by PhI(O₂CCF₃)₂. 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.