The ligands 2-(dimethoxymethyl)pyridine (L¹) and 2,6-bis(dimethoxymethyl)pyridine (L²) formed bidentate chelate complexes with the isoelectronic transition metal moieties Re^IX(CO)₃ and Pt^IVXMe₃ (X = halide). The complexes [ReX(CO)₃L¹] (X = Cl or Br), [PtXMe₃L¹] (X = Br or I) and [ReBr(CO)₃L²] in organic solvents were shown by NMR to undergo fluxional processes which interconvert co-ordinated and pendant OMe groups. Rates and activation energies of these fluxions were measured by NMR methods (1-dimensional bandshape analysis or 2-dimensional exchange spectroscopy). Magnitudes of ΔG^‡ (298.15 K) for the fluxions were in the range 59–85 kJ mol⁻¹ with the order being Re^I–L¹ > Re^I–L² > Pt^IV–L¹. A carbon–carbon bond rotation mechanism is proposed for the fluxions in the L¹ complexes and concerted C–C bond rotation/metallotropic shift processes for the L² complexes. Crystal structures of [ReCl(CO)₃L¹] and [PtIMe₃L¹] revealed distorted octahedral metal centres with N–M–O ‘bite’ angles of 73–75° and a trans relationship of the axial halide and pendant OMe group.

中文翻译：

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动态NMR研究）（I）和铂（IV）络合物中2-（二甲氧基甲基）吡啶和2,6-双（二甲氧基甲基）吡啶的通量

这 配体 2-（二甲氧基甲基）吡啶（L ¹）和2,6-双（二甲氧基甲基）吡啶（L ²）与等电子过渡金属部分Re ^I X（CO）₃和Pt ^IV XMe ₃（X = 卤化物）。有机物中的[ReX（CO）₃ L ¹ ]（X = Cl或Br），[PtXMe ₃ L ¹ ]（X = Br或I）和[ReBr（CO）₃ L ² ]溶剂 被显示 核磁共振经历相互协调的和悬垂的OMe基团互通的通量过程。费率和激活 这些通量的能量通过 核磁共振 方法（一维带状分析或二维 交换光谱）。通量的ΔG ^‡（298.15 K）的大小范围为59–85 kJ mol ^-1，顺序为Re ^I –L ¹  > Re ^I –L ²  > Pt ^IV –L ¹。碳-碳键的旋转机构被提出了fluxions的L ^1种复合物和协调一致C-C键的旋转/ metallotropic换档过程对于L ^2种复合物。[RECL（CO）的晶体结构₃大号¹ ]和[PTIME ₃大号¹ ]揭示了与N-M-O '咬'扭曲的八面体的金属中心的73-75°的角度和一个反 轴向关系 卤化物 和吊坠OMe组。