O'Callaghan Charley, Greenacre Victoria K, King Rhys P, Grigg Julian, Herniman Julie M, McRobbie Graeme, Reid Gillian
School of Chemistry, University of Southampton, Southampton SO17 1BJ, UK.
GE HealthCare, Pollards Wood, Nightingales Lane, Chalfont St Giles, Bucks, HP8 4SP, UK.
Dalton Trans. 2024 Sep 10;53(35):14897-14909. doi: 10.1039/d4dt02074j.
Three amide-functionalised tacn macrocyclic derivatives (tacn = 1,4,7-triazacyclononane) are reported, two tris-amide derivatives, L1 containing three -CHC(O)NHPh pendant arms, L2 containing three -CHCHC(O)NHPr pendant arms, and one -amide, L3, containing Pr groups on two of the tacn amine functions and a single -CHC(O)NHPh function on the third. The reactions of these new ligands towards [MF(dmso)(OH)] (M = Al, Ga) and towards FeF·3HO in alcoholic solution afford the complexes [MF(L)] (L = L1-L3) in good yields as powdered solids. These complexes are characterised by IR and multinuclear NMR spectroscopy (diamagnetic species only) and mass spectrometry. [GaF(L1)], [GaF(L3)] and [FeF(L3)] are also characterised by single crystal X-ray analysis. The corresponding reactions involving [InF(dmso)(OH)] yield mixtures of products (along with F), consistent with the M-F bond strengths decreasing as group 13 is descended. A few crystals of the target complex, [InF(L2)], were also obtained from one such reaction. All of the complexes adopt -octahedral coordination the amine N-donor atoms and retain the three fluoride ligands both in solution and in the solid state. Extensive intramolecular hydrogen-bonding involving the amide NH pendant groups and the MF moieties is evident in the crystal structures. In the isostructural [MF(L3)] (M = Ga, Fe) complexes the head-to-tail C(O)NH⋯F H-bonded dimers observed in the solid state resemble those found frequently in organic compounds and that form the cornerstone of many supramolecular assemblies. This is consistent with the MF fragments being strong H-bond acceptors. Radiofluorination of [GaF(L1)] by F/F isotopic exchange in MeOH at 3 μmol mL precursor concentration and using aqueous [F]F in target water (75% : 25%) with gentle heating (80 °C, 10 min) gave . 20% radiochemical yield of [GaFF(L1)]. In contrast, no F incorporation occurs with [GaF(L3)] under any of the conditions explored.
报道了三种酰胺官能化的tacn大环衍生物（tacn = 1,4,7 - 三氮杂环壬烷），两种三酰胺衍生物，L1含有三个 -CHC(O)NHPh侧链臂，L2含有三个 -CHCHC(O)NHPr侧链臂，以及一种酰胺L3，在tacn的两个胺官能团上含有丙基，在第三个胺官能团上含有单个 -CHC(O)NHPh官能团。这些新配体在醇溶液中与[MF(dmso)(OH)]（M = Al、Ga）以及与FeF·3HO的反应以良好的产率得到粉末状固体配合物[MF(L)]（L = L1 - L3）。这些配合物通过红外光谱和多核NMR光谱（仅抗磁性物种）以及质谱进行表征。[GaF(L1)]、[GaF(L3)]和[FeF(L3)]还通过单晶X射线分析进行表征。涉及[InF(dmso)(OH)]的相应反应产生产物混合物（连同F），这与随着第13族元素原子序数增加M - F键强度降低一致。从这样的一个反应中也获得了少量目标配合物[InF(L2)]的晶体。所有配合物均采用八面体配位，胺氮供体原子，并且在溶液和固态中都保留三个氟配体。在晶体结构中明显存在涉及酰胺NH侧链基团和MF部分的广泛分子内氢键。在同构的[MF(L3)]（M = Ga、Fe）配合物中，在固态中观察到的头对尾C(O)NH⋯F氢键二聚体类似于在有机化合物中经常发现的那些，并且构成许多超分子组装体的基石。这与MF片段是强氢键受体一致。在3 μmol mL前体浓度下，在MeOH中通过F/F同位素交换对[GaF(L1)]进行放射性氟化，并使用目标水中的水性[F]F（75%∶25%）并温和加热（80 °C，10分钟），得到[GaFF(L1)]的放射化学产率为20%。相比之下，在探索的任何条件下，[GaF(L3)]都不发生F掺入。
