Transforming the Greenhouse Gas Fluoroform into a Bench-Stable Reagent for Trifluoromethylation Using an Aluminum-Based Metal-Organic Framework

Fluorochemicals are central to the modern medicinal, agrochemical, and polymer industries, yet the sustainability of fluorochemical synthesis is challenged by an over-reliance on non-renewable fluorine sources such as fluorospar (CaF2). Recycling fluorinated waste represents a promising solution to this challenge, but to date there are limited platforms that enable both the capture of fluorinated waste products and their subsequent conversion into value-added products. Herein, we demonstrate that the robust and inexpensive Al-based metal-organic framework (MOF) MIL-160 (MIL = Matériaux de l′Institut Lavoisier) enables the capture of the waste greenhouse gas fluoroform (CHF3), a byproduct of semiconductor and fluoropolymer manufacturing, from mixtures of other fluorinated gases and from dilute emission streams. MIL-160 exhibits record-setting adsorption of CHF3 at low pressures (3.88 mmol g−1 at 0.1 bar and 298 K) and selectivity over N2 (10:90 CHF3/N2 IAST selectivity of S = 1504) owing to its unique crown ether-like binding pocket for CHF3. CHF3-loaded MIL-160 can be stored long-term and employed directly in a range of nucleophilic and metal-mediated trifluoromethylation reactions. Thus, our findings establish the first integrated strategy for the separation, storage, and utilization of CHF3, providing a pathway for transforming an environmentally problematic waste gas into a synthetically valuable reagent.