The Mechanisms of Making Molecules to Order

摘要: The mechanisms of formation a [2]catenane and one its molecular components have been investigated. While the synthesis tetracationic cyclophane, [BBIPYBIXYCY]4+ from bipyridine (BP) 1,4-bis(bromomethyl)benzene (BBB), directed by template, 1,5–bis[2(2–hydroxyethoxy)ethoxy]naphthalene(1/5BHEEN) becomes less efficient (23 to 5%) under ultra-high pressure reaction conditions (12 kbars), self-assembly {[2]-[BPP34C10]-[BBIPYBIXYCY] catenane}4+ BP BBB in presence BPP34C10 can be achieved with increased efficiency (18 42%) at 12 kbars. This difference trends yields ascribed enhanced templating action relative that 1/5BHEEN when two moles are being employed construct cyclophane. BP, BBB, has followed 1H NMR spectroscopy D7-DMF solution. On basis this spectroscopic evidence supporting chemical data, mole is believed proceed via monoquatemary intermediate, [MBXYBIPY]+, which not isolated, dicationic species, [BBIPYXY]2+, isolated shown an intermediate process leading [2]catenane, presumably [BXYBBIPYXY]3+ trication — final again isolated.