Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35032 Marburg, Germany.
Magn Reson Chem. 2009 Dec;47(12):1024-30. doi: 10.1002/mrc.2506.
The conformation of [bis-(N,N'-difluoroboryl)]-3,3'-diethyl-4,4',8,8',9,9',10,10'-octamethyl-2,2'-bidipyrrin (1) in solution was studied by analyzing the 13C-19F and 19F-19F through-space spin-spin couplings. The 1H and 13C NMR spectra were assigned on the basis of nuclear Overhauser effect spectroscopy (NOESY), heteronuclear single-quantum correlation (HSQC), and heteronuclear multiple-bond correlation (HMBC) experiments. The 19F spectrum of 1 was compared with that of 2-ethyl-1,3,5,6,7-pentamethyl-4,4-difluoro-4-bor-3a,4a-diaza-s-indacen (2). The 19F-19F through-space spin--spin coupling in 1 was thus assigned and the coupling constant was obtained by simulating the coupling patterns. The obtained conformation of 1 was compared with those of the known complexes [bis-(N,N'-difluoroboryl)]-3,3',8,8',9,9'-hexaethyl-4,4',10,10'-tetramethyl-6,6'-(4-methylphenyl)-2,2'-bidipyrrin (3)and [bis-(N,N'-difluoroboryl)]-9,9'-diethyl-4,4',8,8',10,10'-hexamethyl-3,3'-bis(methoxycarbonylethyl)-2,2'-bidipyrrin (4). The conformational dynamics of 1, 3, and 4 was surveyed by observing the temperature dependence of the through-space coupling constants between 253 and 333 K. The 13C-19F and 19F-19F through-space spin-spin couplings thus confirm similar conformations of different BisBODIPYs in solution in contrast to earlier findings in the solid state.
[双（N,N'-二氟硼基）]-3,3'-二乙基-4,4',8,8',9,9',10,10'-八甲基-2,2'-双二吡咯甲烷（1）在溶液中的构象通过分析 13C-19F 和 19F-19F 通过空间自旋-自旋偶合来研究。根据核奥弗豪瑟效应光谱（NOESY）、异核单量子相关（HSQC）和异核多键相关（HMBC）实验，对 1H 和 13C NMR 谱进行了分配。将 1 的 19F 光谱与 2-乙基-1,3,5,6,7-五甲基-4,4-二氟-4-硼-3a,4a-二氮杂-s-吲哚（2）的 19F 光谱进行了比较。因此，对 1 中的 19F-19F 通过空间自旋-自旋偶合进行了分配，并通过模拟偶合模式获得了偶合常数。将获得的 1 的构象与已知配合物[双（N,N'-二氟硼基）]-3,3',8,8',9,9'-六乙基-4,4',10,10'-四甲基-6,6'-(4-甲基苯基）-2,2'-双二吡咯甲烷（3）和[双（N,N'-二氟硼基）]-9,9'-二乙基-4,4',8,8',10,10'-六甲基-3,3'-双（甲氧基羰基乙基）-2,2'-双二吡咯甲烷（4）的构象进行了比较。通过在 253 至 333 K 之间观察通过空间偶合常数的温度依赖性，研究了 1、3 和 4 的构象动力学。13C-19F 和 19F-19F 通过空间自旋-自旋偶合证实了不同 BisBODIPY 在溶液中的构象相似，与以前在固态中的发现相反。
