• carbon capture
• porous materials
• metal organic frameworks
• zirconium
• defects

Zirconium-based metal-organic frameworks (Zr-MOFs) are one of the most attractive classes of MOF materials, due to their superior chemical, thermal, and mechanical stability. Unlike other MOFs, Zr-based MOFs crystal structures can contain unusually large amounts of defects without undergoing severe loss of stability. This feature makes Zr-MOFs unique among MOF materials. The first Zr-MOFs discovered, and since then, one of the most widely studied and used, is UiO-66. The purpose of this work is to synthesize highly defective UiO-66 materials and use them as substrates for post-synthetic defect exchange reactions, resulting in defect-engineered materials. We covalently bind aliphatic amines both Boc-protected and not, such as glycine, β-alanine, γ-aminobutyric acid, and 5-aminovaleric acid to UiO-66 defects, for post-combustion capture applications. We developed a novel thermal Boc-deprotection protocol, tailored for grafted-at-defects amines. Gas sorption analysis reveals that amine-functionalized UiO-66 materials do not chemically interact with CO2, despite being -NH2 containing materials. Interestingly, we found that UiO-66 catalyzes GABA intramolecular cyclization, resulting in 2-pyrrolidone.