Fluorination-18F using tri-tert-butanol ammonium iodide as phase-transfer catalyst: an alternative minimalist approach was written by Shinde, Sandip S.;Bolik, Kim-Viktoria;Maschauer, Simone;Prante, Olaf. And the article was included in Pharmaceuticals in 2021.HPLC of Formula: 936902-12-4 This article mentions the following:
The 18F syntheses of tracers for positron emission tomog. (PET) typically require several steps, including extraction of [18F]fluoride from H2[18O]O, elution, and drying, prior to nucleophilic substitution reaction, being a laborious and time-consuming process. The elution of [18F]fluoride is commonly achieved by phase transfer catalysts (PTC) in aqueous solution, which makes azeotropic drying indispensable. The ideal PTC is characterized by a slightly basic nature, its capacity to elute [18F]fluoride with anhydrous solvents, and its efficient complex formation with [18F]fluoride during subsequent labeling. Herein, we developed tri-(tert-butanol)-methylammonium iodide (TBMA-I), a quaternary ammonium salt serving as the PTC for 18F-fluorination reactions. The favorable elution efficiency of [18F]fluoride using TBMA-I was demonstrated with aprotic and protic solvents, maintaining high 18F-recoveries of 96-99%. 18F-labeling reactions using TBMA-I as PTC were studied with aliphatic 1,3-ditosylpropane and aryl pinacol boronate esters as precursors, providing 18F-labeled products in moderate-to-high radiochem. yields. TBMA-I revealed adequate properties for application to 18F-fluorination reactions and could be used for elution of [18F]fluoride with MeOH, omitting an addnl. base and azeotropic drying prior to 18F-labeling. We speculate that the tert-alc. functionality of TBMA-I promotes intermol. hydrogen bonding, which enhances the elution efficiency and stability of [18F]fluoride during nucleophilic 18F-fluorination. In the experiment, the researchers used many compounds, for example, 5-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)benzo[d]oxazole (cas: 936902-12-4HPLC of Formula: 936902-12-4).
5-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)benzo[d]oxazole (cas: 936902-12-4) belongs to benzoxazole derivatives. Benzoxazoles belong to the group of well-known antifungal agents with antioxidant, antiallergic, antitumoral and antiparasitic activity. Due to its versatile biological properties, benzoxazole has been incorporated as an essential pharmacophore and substructure in many medicinal compounds.HPLC of Formula: 936902-12-4
Referemce:
Benzoxazole – Wikipedia,
Benzoxazole | C7H5NO – PubChem