双(取代水杨醛)缩卡巴肼及其苄基锡配合物的合成、表征、荧光性质和除草活性

用5-甲基水杨醛、4-二乙氨基水杨醛分别与卡巴肼或硫代卡巴肼缩合,制得1,5-二取代卡巴肼或硫代卡巴肼配体。在微波甲醇溶剂热条件下,二苄基二氯化锡前体与配体反应,合成了双(取代水杨醛)缩(硫代)卡巴肼苄基锡配合物T1～T4,但T4的结构与T1～T3不同,T4由N,N′-双(4-二乙氨基水杨醛)缩连氮及甲氧基桥联锡组成的苄基锡配合物,T4还可由卡巴肼、4-二乙氨基水杨醛和二苄基二氯化锡"一锅法"合成。T1～T4的结构经元素分析、IR、1H/13C NMR表征,并用X射线衍射法确证配合物T4的晶体分子结构。T4属单斜晶系,P21/c空间群,中心锡原子与氮、氧、苄基碳和氯原子组成六配位变形八面体构型。T4在DMF-H2O溶液中具有良好的荧光性质,当含水量0～30%(V/V)时具有聚集荧光增强效应,含水量大于30%时,随含水体积分数增加荧光强度减弱,以至最后淬灭。配合物对马齿苋具有良好的生长抑制作用,T1和T3对决明子、T2对苋菜和T4对四九菜心具有选择性生长抑制作用,可作为除草剂的候选化合物进一步研究。

Synthesis, Characterization, Fluorescence Properties and Herbicidal Activity of Bis(Substituted Salicylaldehyde) Carbohydrazide and Its Benzyltin Complexes

The 1,5-disubstituted carbohydrazide and thiocarbohydrazide ligands were prepared by condensation of carbohydrazide, thiocarbohydrazide with 5-methylsalicylaldehyde, 4-diethylaminosalicylaldehyde, respectively. Their benzyltin complexes, T1~T4 were obtained by microwave-assisted solvothermal reaction of dibenzyltind-ichloride precursor with the ligands in methanol environments. However, the structure of T4 is different from those of T1~T3, which is a benzyltin complex bridged by N,N''-bis(4-diethylaminosalicylaldehyde) azine and methoxy group. Also, T4 can be synthesized by the "one pot" method of carbohydrazide, 4-diethylaminosalicylal-dehyde and dibenzyltindichloride. Their structures are characterized by elemental analysis, IR, ¹H/¹³C NMR spectra, and the molecular structure of complex T4 was confirmed by X-ray diffraction. The crystal of T4 belongs to monoclinic system, space group P2₁/c. The Sn atom is six-coordinated with distorted octahedral geometry formed by O, N atoms from the carbohydrazide ligand, C atom of butyl and two Cl atoms. The complex T4 has strong fluorescence emission in DMF and mixed solvents of DMF-water. When the volume fraction of water is 0~30% (V/V), the aggregation fluorescence enhancement effect is good, and fluorescence quenching occurs when the water content is more than 30% (V/V). The complexes have good growth inhibition on Portulaca oleracea L., and T1 and T3 have selective growth inhibition on Cassia tora L., T2 on Amaranthus tricolor L., T4 on Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee. They can be used as candidate herbicides for further study.