这项审查涉及全氟烷基碘化物(R F I)在各种结构的有机物质的合成中的自由基化学。R F I的自由基链反应很容易由偶氮腈引发剂引发,该过程通常可从许多类型的不饱和化合物中获得纯净的产物。该过程称为碘全氟烷基化。在合成含氟有机化合物中,很少有方法可以与R F I自由基加成的效率,成本,选择性和多功能性进行比较。第一部分回顾了从R F I生成R F自由基用于合成目的的所有方面并报告R F的相对反应性I和20个典型的烯烃或炔烃。通过实例和实验数据综合表说明了16种不同类别的烯烃和炔烃的实用合成。特别强调了许多这些新的全氟烷基取代的化合物的新颖重要用途。这篇综述的目的是在50年的时间里,将R F I的研究结果集中到一起,作为含氟有机化合物合成的一个切入点。在本文的后续部分中,还将处理其他类别的化合物。
2-Iodo-3-perfluoroalkylpropyl acetates, RFCH2CHICH2OAc (1) (RF = i-C3F7, C4F9, C6F13, C8F17), have been rearranged thermally to 1-iodo-3-perfluoroalkyl-2-propyl acetates, RFCH2CH(OAc)CH2I (2), in 89% yield over the temperature range 120–200 °C. The results indicate that the rearrangement is a reversible process which is shifted towards the formation of 2. The equilibrium regio isomer ratio (12 = 1:8)
乙酸2-碘-3-全氟烷基丙基酯R F CH 2 CHICH 2 OAc(1)(R F = iC 3 F 7,C 4 F 9,C 6 F 13,C 8 F 17)已热重排为1 -碘-3-全氟烷基-2-丙基乙酸酯,R F CH 2 CH(OAc)CH 2 I(2),在120–200°C的温度范围内,产率为89%。结果表明,重排是一个可逆的过程,向2的形成转移。。平衡区域异构体比率(12 = 1:8)与温度和R F取代基的性质无关。提出重排通过自由基机理进行,所述自由基机理包括在C 1 I键热断裂后乙酰氧基的1,2-迁移。
Radical-induced reaction of monoiodo- and diiodo-perfluoroalkanes with allyl acetate: telomer and rearranged products, mass-spectral distinguishing of regioisomers
(2a-c)] and 2:1 telomers (5a-c) underwent subsequent thermal rearrangement [formation of RFCH2CH(OCOCH3)CH2I, (3a-c), and telomers (6a-c), respectively] at elevated temperatures. In the reaction of diiodides IQI, monoadducts [CH3COOCH2CHICH2QI, (9a,b)] and diadducts [(CH3COOCH2CHICH2)2Q (10a,b)] were formed, but no telomeric and rearrangedproducts were found under the reaction conditions employed. On the
过氧化引发剂引发的单碘全氟烷烃R F I(R F = C 4 F 9,C 6 F 13,C 8 F 17)和二碘全氟烷烃IQI(Q = C 4 F 8,C 6 F 12)与乙酸烯丙酯的自由基反应描述。在所采用的反应条件下,大多数情况下,R F I和IQI的转化均完成。R F的反应我还产生了一些2:1端粒,它们是已表征的新化合物。在某些情况下,以高达34%的制备产率分离端粒。1:1的加合物[R F CH 2 CHICH 2 OCOCH 3,(2a-c) ]和2:1的端粒(5a-c)都进行了后续的热重排[R F CH 2 CH(OCOCH 3)CH 2 I的形成,(3a-c)和端粒(6a-c) ]。在二碘化物IQI的反应中,单加合物[CH 3 COOCH 2 CHICH 2 QI,形成(9a,b) ]和二加合物[(CH 3 COOCH 2 CHICH 2)2 Q(10a,b)],但在所采用的反
Reaction of perfluoroalkyl iodides with electron-donor nucleophiles. Addition of perfluoroalkyl iodides to olefins initiated by electron transfer
作者:Andrew E. Feiring
DOI:10.1021/jo00218a006
日期:1985.9
Highly selective synthesis of [(perfluoroalkyl) methyl] oxiranes (by the addition of iodoperfluoroalkanes to allyl acetate)
Mixtures of regioisomeric adducts of monoiodoperfluoroalkanes R-F-I (R-F = C4F9, C6F13 C8F17) with allyl acetate, RFCH2CHICH2OAc (1a-1c) and rearranged adducts RFCH2CH(OAc)-CH2I (2a-2c), were converted chemoselectively to the corresponding oxiranes RFCH2CH(-O-)CH2 (3a-3c) in yields of 94-96% (total yields of the two-step synthesis starting from R-F-I were 85-87%). The chemoselectivity of the oxirane formation appeared to be very dependent on the solvent used. Dependence on the reaction conditions on formation of byproducts RFCH=CHCH2OAc (4a-4c) and RFCH=CHCH2OH (5a-5c) in the epoxidation reaction was studied. (C) 1997 Elsevier Science S.A.