| Abstract
| - Reactions of 2,6-dibromo-, 3,5-dibromo-, and 2,4,6-tribromopyridine with IZnCH2CH2Rf8 (Rf8 =(CF2)7CF3) in THF at 65 °C in the presence of trans-Cl2Pd(PPh3)2 (5 mol %) gave the fluorouspyridines 2,6- and 3,5-NC5H3(CH2CH2Rf8)2 (1 and 2; 85%, 31%) and 2,4,6-NC5H2(CH2CH2Rf8)3 (3,61%). Reaction of 2,6-pyridinedicarboxaldehyde with [Ph3PCH2CH2Rf8]+I-/K2CO3 (p-dioxane/H2O,95 °C) gave 2,6-NC5H3(CHCHCH2Rf8)2 (95%; 70:30 ZZ/ZE), which was treated with H2 (1 atm, 12h) and 10% Pd/C to yield 2,6-NC5H3(CH2CH2CH2Rf8)2 (5, 95%), a higher homologue of 1. Longerreaction times afforded piperidine cis-2,6-HNC5H8(CH2CH2CH2Rf8)2 (6, 98%). The stereochemistrywas established by NMR analysis of the N-benzylpiperidine. Pyridines 1−3 and 5 are low-meltingwhite solids with CF3C6F11/toluene partition coefficients (24 °C) of 93.8:6.2, 93.9:6.1, >99.7:<0.3,and 90.4:9.6, respectively (6, 93.6:6.4). Reaction of 1 and CF3SO3H gave a pyridinium salt, andCl2Pd(NCCH3)2 (0.5 equiv) yielded trans-Cl2Pd(1)2. The crystal structure of the former, which alsoexhibited liquid crystalline and ionic liquid phases, was determined.
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