Synthesis, Structural Characterization, Fluorescence Properties and Herbicidal Activity of Bis(substituted salicylaldehyde) Carbohydrazide Dibutyltin Complexes

A series of dibutyltin complexes,（Bu;Sn）;L,[（Bu;Sn）;L];and H;LSnBu;,were synthesized by microwave-assisted methanolic solvothermal method,where H;L is[2-（OH）-R-Ar CH=NNH];CX,and X=O,R=4-NEt;（T1）,5-Br （T2）;X=S,R=H （T3）;R=5-Br （T4）.Their structures were characterized by elemental analysis,IR and (;H,;C)-NMR spectra.The molecular structure of T2 was confirmed by X-ray diffraction.The crystal of T2 belongs to monoclinic system,space group Ia.Five-coordinated distorted triangular bipyramids and six-coordinated distorted octahedral configurations were formed by the coordination of oxygen and nitrogen atoms of ligand with two dibutyltins,thus forming a trimeric hexanuclear butyltin complex by the cross coordination of three units （Bu;Sn）;L with enol imines.The T2 and T4 exhibit fluorescence emission in DMF solvents and DMF-water mixture.The fluorescence intensity of T2-DMF-H;O system decreases almost linearly with the increase of water volume fraction （WVF）.The aggregation fluorescence enhancement effect of T4-DMF-H;O solution system increases with the increase of WVF at the range of 0～20%WVF.When WVF is more than 20%,the fluorescence intensity decreases with the increase of WVF.In addition,T1～T4 have broad growth activities on target plants,such as Portulaca oleracea L.,Amaranthus spinosus L.,Cassia tora L.,Brassica campestris L.ssp.chinensis var.utilis Tsen et Lee,and Amaranthus tricolor L.,and can be used as a candidate herbicide for further research.