Department of Chemistry, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do 440-746, Korea.
Department of Applied Chemistry, Kyung Hee University 1732, Duckyoung-daero 1732, Gihung-gu, Yongin-si, Gyeonggi-do 446-701, Korea.
Chem Soc Rev. 2016 Aug 22;45(17):4638-50. doi: 10.1039/c6cs00286b.
Due to the tremendous interest in carbon-fluorine bond-forming reactions, research efforts in this area have been dedicated to the development of facile processes to synthesize small fluorine-containing organic molecules. Among others, PET (Positron Emission Tomography) is one of the most important applications of fluorine chemistry. Recognizing the specific requirements of PET processes, some groups have focused on fluorination reactions using alkali metal fluorides, particularly through SN2-type reactions. However, a common "misconception" about the role of protic solvents and hydrogen bonding interactions in this class of reactions has hampered the employment of these excellent promoters. Herein, we would like to review recent discoveries in this context, showing straightforward nucleophilic fluorination reactions using alkali metal fluorides promoted by protic solvents. Simultaneous dual activation of reacting partners by intermolecular hydrogen bonding and the enhancement of the "effective fluoride nucleophilicity", which is Nature's biocatalytic approach with the fluorinase enzyme, are the key to this unprecedentedly successful nucleophilic fluorination.
由于对碳-氟键形成反应的极大兴趣，该领域的研究致力于开发简便的方法来合成含氟小分子有机化合物。其中，正电子发射断层扫描（Positron Emission Tomography，PET）是氟化学最重要的应用之一。一些研究小组认识到 PET 工艺的特殊要求，专注于使用碱金属氟化物进行氟化反应，特别是通过 SN2 型反应。然而，关于质子溶剂和氢键相互作用在这类反应中的作用的一个常见“误解”阻碍了这些优秀催化剂的应用。本文将综述这方面的最新发现，展示使用质子溶剂促进的碱金属氟化物进行的直截了当的亲核氟化反应。通过分子间氢键同时对反应伙伴进行双重活化，以及增强“有效氟亲核性”，这是氟酶生物催化方法的关键，这种方法是自然界前所未有的成功亲核氟化的关键。
