The structure of the 2-((E)-((Z)-3-(((4-hydroxyphenyl)amino)methylene)-4-oxocyclohexa-1,5-dien-1-yl)diazenyl)benzoic acid (H₃L) was confirmed by single crystal X-ray diffraction and Hirshfeld surface analysis was used further to quantify the intermolecular interactions. It crystallized in monoclinic space group P2₁/c. The observed bond distances evidence that the structure exists predominately in azo-enamine tautomeric form in the solid state. A novel dibutyltin(IV) complex, [(Bu₂SnHL)₂] (1) was synthesized from H₃L. The complex was then characterized by studying different techniques including elemental analysis, FT-IR, and NMR (¹H, ¹³C, and ¹¹⁹Sn) spectroscopy. In solution state, the molar mass of the compound was confirmed by Mass spectrometry. Spectroscopy study guides to predict the structure of the complex which is supposed to be a cyclic dimer [(Bu₂SnHL)₂] and Sn(IV) adopts a six-coordinated geometry. However, in solution Sn(IV) adopts four coordinated distorted tetrahedral geometry which was supported by ¹¹⁹Sn NMR spectroscopy (δ_Sn(119), 126.34 ppm) and EI-MS results of the complex ion ([C₂₈H₃₂N₃O₄Sn]⁺,m/z 593.1). Further, the structures in solid and solution state were supported by developing their optimized structures and IR data from the DFT calculation.

Graphical Abstract

The crystal structure of the ligand is in azo-enamine tautomeric form and in accordance with DFT study, its dibutyltin(IV) complex is a cyclic dimer, (Bu₂SnHL)₂, which becomes monomer in solution.

中文翻译：

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2-((E)-((Z)-3-(((4-羟基苯基)氨基)亚甲基)-4-氧代环己-1,5-二烯-1-基)二氮烯基)苯甲酸的晶体结构和合成，其二丁基锡(IV)络合物的光谱和DFT研究

2-(( E )-(( Z )-3-(((4-羟基苯基)氨基)亚甲基)-4-氧代环己-1,5-二烯-1-基)二氮烯基)苯甲酸的结构( H ₃ L）通过单晶 X 射线衍射得到证实，并进一步使用赫什菲尔德表面分析来量化分子间相互作用。它以单斜空间群P 2 ₁ /c结晶。观察到的键距证明该结构主要以固态的偶氮烯胺互变异构形式存在。_{由 H 3} L合成了一种新型二丁基锡 (IV) 配合物 [(Bu ₂ SnHL) ₂ ] ( 1 )。然后通过研究元素分析、FT-IR 和 NMR 等不同技术对该配合物进行表征 ( ¹ H, ¹³ C和¹¹⁹ Sn)光谱。在溶液状态下，通过质谱法确认化合物的摩尔质量。光谱学研究指导预测复合物的结构，该复合物被认为是环状二聚体[(Bu ₂ SnHL) ₂ ]，并且Sn(IV)采用六配位几何形状。然而，在溶液中Sn(IV)采用四配位扭曲四面体几何形状，这得到了¹¹⁹ Sn NMR 光谱 (δ _Sn(119) , 126.34 ppm) 和络离子 ([C ₂₈ H ₃₂ N ₃ O ₄ Sn] ⁺，m/z 593.1)。此外，通过开发优化结构和 DFT 计算的红外数据，支持固态和溶液状态的结构。

图形概要

该配体的晶体结构为偶氮-烯胺互变异构形式，根据DFT研究，其二丁基锡(IV)配合物是环状二聚体(Bu 2 _SnHL ) ₂，在溶液中变成单体。