Self-assembled Organotin(?)Carboxylate Moieties With N-phenyl-o-aminobenzoic Acid:Synthesis,Characterizations,Crystal Structures And Properties

Self-assembled organotin?IV?carboxylate,as a kind of important metal-organic compounds have a wide range of application prospect in the clinical medicine,industry and agriculture owing to their various structures and multiple properties such as antitumor activity,sterilization,mite-killing ablity and two-photon absorption.It has been a research hotspot to select organic oxyacids as electron donors and hydrocarbyl tin oxide or stannic acid to self assemble them into new organotin carboxylates.In this article,a series of new organotin?IV?carboxylate derivatives:?Bu₂SnO?₄?OOCPhNHPh?₄?1??CH₃PhSnOPhCH₃?₆?OOCPhNHPh?₆?2?and?BuSnOOH?₆?OOCPhNHPh?₆?3?were synthesized by the reaction of 2-?phenylamino?benzoic acid and dibutyltin oxide,p-methylphenyl tin oxide and butyltinic acid for 10 h in the toluene,respectively.Toluene was selected as the best reaction solvent,and the best solvent quantity and reaction time were determined.The reaction temperature is the reflux temperature of the solvent and the self-assembly reaction was completed by dehydration.All the complexes 1-3 have been characterized by IR,¹H NMR,¹³C NMR spectra.The single crystal structures of complexes 1-3 were determined by X-ray crystallography diffraction analyses.According to the crystal structure,the compound 1 is a short trapezoidal-like dimer with the SnO₂ as the center,which forms a three-dimensional supramolecular structure with C-H…? and N-H…O.And the compound 2 and 3 are drum-like.It can be proved that tin dihydroxylate is easy to be assembled into muti-core polymer,and the monohydroxytin is easy to be assembled into the drum-like structure.The ligand of compound 2 has a rigid plane,while the ligand of compound 3 is flexibility,so the distortion level of the compound 3 more lower than the compound 2.It can be found that the distortion level of drum-like structure is related to the rigidity of ligand and the alkyl group of substrate.More rigid group means the bigger steric hindrance,and the distortion level of corresponding drum-like structure is higher.In addition,the fluorescence emission spectral of all the compounds were monitored and showed bright blue fluorescence.The maximal emissions of all the compounds were red-shifted comparing to the ligands,and the luminescent intensity of compound 3 are weaker than compound 2.The fluorescence of the compounds come from the electronic transition in the ligands,it can be inferred that the chemical environment of the tin atom has an important impact on the fluorescence intensity.The rigidity of the compound will reduce the energy loss caused by the vibration,the fluorescence intensity will be enhanced.This work enriched the structure of organotin carboxylates,and paved the way for the study of luminous organotin carboxylates as molecular probes to identify the host macromolecules.