| Summary: | <p>All fluorochemicals—including elemental fluorine and nucleophilic, electrophilic, and radical fluorinating reagents—are prepared from hydrogen fluoride (HF). This highly toxic and corrosive gas is produced by the reaction of acid-grade fluorspar (>97% CaF<sub>2</sub>) with sulfuric acid under harsh conditions. The use of fluorspar to produce fluorochemicals via a process that bypasses HF is highly desirable but remains an unsolved problem because of the prohibitive insolubility of CaF<sub>2</sub>. Inspired by calcium phosphate biomineralization, we herein disclose a protocol of treating acid-grade fluorspar with dipotassium hydrogen phosphate (K<sub>2</sub>HPO<sub>4</sub>) under mechanochemical conditions. The process affords a solid composed of crystalline K<sub>3</sub>(HPO<sub>4</sub>)F and K<sub>2−</sub><em><sub>x</sub></em>Ca<em><sub>y</sub></em>(PO<sub>3</sub>F)<em><sub>a</sub></em>(PO<sub>4</sub>)<em><sub>b</sub></em>, which is found suitable for forging sulfur-fluorine and carbon-fluorine bonds.</p>
|
|---|