Efficient deprotection of F-BODIPY derivatives: removal of BF₂ using Brønsted acids

• Mingfeng Yu,
• Joseph K.-H. Wong,
• Cyril Tang,
• Peter Turner,
• Matthew H. Todd and
• Peter J. Rutledge

Beilstein J. Org. Chem. 2015, 11, 37–41, doi:10.3762/bjoc.11.6

• ) effects this conversion in near-quantitative yields. Compared to existing methods, these conditions are relatively mild and operationally simple, requiring only reaction at room temperature for six hours (TFA) or overnight (HCl). Keywords: Brønsted acids; click chemistry; deboration; dipyrrins; F-BODIPYs

• : potassium tert-butoxide in tert-butanol/water with microwave heating to 90–140 °C (26–98% yield) [15][16]. Kusaka et al. built on this strategy to achieve deboration of F-BODIPYs using sodium tert-butoxide in refluxing toluene (59–83% yield) en route to bis(dipyrrinato)zinc(II) complexes [17]. Two very

• corresponding 3-amino- and 3-acetamido-F-BODIPY precursors, using ‘HCl-catalyzed deacetylation conditions’ (HCl in ethanol) to effect both deacetylation and deboration [34]. Conclusion In conclusion, we have serendipitously achieved efficient removal of the BF2 moiety from F-BODIPY derivatives using either the