有机氟化合物.pptVIP

有机氟化学发展史上的里程碑 1771年：HF (Scheele) 1886年：F2 ( Moissan) 1896年: 氟代乙酸乙酯的合成 20世纪30年代: 含氟制冷剂的合成 1938年：美国杜邦公司偶然发现的聚四氟乙烯 二次世界大战期间：曼哈顿工程的实施(全氟化合物) 1954年：高生理活性的氟代氢化可的松的合成 有机氟化学从诞生起一直和社会需求紧密地联系在一起。社会对有机氟化合物的需求推动了有机氟化学学科的发展 含氟材料 耐高温、耐酸碱、耐氧化、室外耐久性 低表面张力--疏水、疏油等 1943：PTFE (工业化) 不易加工；不透明 1989：Teflon AF (combine the chemical inertness of PTFE with optical transparency and process ability) 用不同折射率的Taflon AF作芯材和皮层材料可研制用于280℃“超级光纤” 含氟麻醉剂 Effects of Fluorine on Biological Reactivity 1) the high carbon- fluorine bond strength (108 Kcal/mole) renders the fluorine substituent resistant to many such metabolic transformations Vitamin D3 2) Fluorine may also be employed as a leaving group in addition-elimination processes where its superior leaving group ability relative to hydrogen is important. Such applications have led to the development of very effective mechanism-based enzyme inhibitors. 3) Fluorine on a carbon adjacent to the carbonyl group increases the electrophilicity of the carbonyl carbon and therefore the tendency of nucleophiles to add. Inhibition is probably due to the formation of a stable hemiketal with the active site 4) Fluorine has been employed as a replacement for both hydroxyl and hydrogen Difluoromethylene units have been employed as isosteric replacements for oxygen In fact, no other functional group that can replace oxygen matches so well the steric and electronic demand of oxygen. The Csp3-F bond of 1.40A°is slightly shorter than the Csp3-OH bond Competitive inhibitor of acylCoA:cholesterol acyltransferase Angew. Chem. Int. Ed., 2001, 40, 4461 5) Fluorine has been identified as improving the lipophilicity of a molecule and hence its distribution within an organism. CF3 group the lipophilicity of substituents X ? SCF3 +1.58 OCF3