Tritiodefluorination of alkyl C─F groups

0510965 - ÚOCHB 2020 RIV GB eng J - Článek v odborném periodiku
Brož, Břetislav - Marek, Aleš
Tritiodefluorination of alkyl C─F groups.
Journal of Labelled Compounds and Radiopharmaceuticals. Roč. 62, č. 11 (2019), s. 743-750. ISSN 0362-4803. E-ISSN 1099-1344
Institucionální podpora: RVO:61388963
Klíčová slova: C-F activation * deuterium labeled alkane * deuterodefluorination * frustrated Lewis pairs * hydrogen activation * non-metallic reagent * tritiodefluorination * tritium labeled alkane * ultra-mild reaction conditions * very low tritium pressure
Obor OECD: Analytical chemistry
Impakt faktor: 1.809, rok: 2019
Způsob publikování: Omezený přístup
https://onlinelibrary.wiley.com/doi/abs/10.1002/jlcr.3782

A straightforward methodology of fluorine substitution by tritium/deuterium is reported. The described method is selective towards the F─C (sp3) group and leaves both the aromatic F─C (sp2) and F2─C (sp3) moieties unaffected. Alkylfluorides, readily synthesized from appropriate alcohols by treatment with diethylaminosulfur trifluoride (DAST) reagent in an overall yield up to 76%, undergoes activation with the boron‐based Lewis acid B(C6F5)3, and stoichiometric in situ reduction with a tritide/deuteride reagent—the [TMP2(3)H][2(3)HB(C6F5)3] system of frustrated Lewis pair. This methodology provides an isolated yield of up to 93% of regio‐specifically labeled small organic compounds with superior 2H‐enrichment of over 95%. The specific activity of prepared 1‐(2‐[3H]‐ethyl)naphthalene was determined at 29.0 Ci/mmol. The site selectivity of the Lewis acid/ [TMP2(3)H][2(3)HB(C6F5)3] approach is orthogonal to currently used methods and allows for isotopic labeling of complementary positions in molecules. Reported labeling methodology proceeds well at ultra‐mild reaction conditions (220 mbar of T2), allowing very low consumption of the radioactive source (4.2 Ci/156 GBq), and producing limited amount of radioactive waste.
Trvalý link: http://hdl.handle.net/11104/0301318