Iron(III) complexes having general formula FeLCl₂ [where, L = 2-acetylpyridine acetoylhydrazone (APAH), 2-acetylpyridine benzoylhydrazone (APBH), 2-acetylthiophene acetoylhydrazone (ATAH), and 2-acetythiophene benzoylhydrazone (ATBH)] have been synthesized and characterized based on molar conductivity, electronic and IR spectroscopy. The structure of iron(III) complex with APBH ligand is determined using single crystal X-ray crystallography. The complex crystallizes in monoclinic space group P21/n with a = 7.8490(6) Å, b = 15.1018(11) Å, c = 13.2263(10) Å, α = 90°, β=100.183(3)°, γ = 90°, V = 1543.1(2) ų and Z = 4 with central Fe(III) ion coordinated by one tridentate APBH ligand. The iron is involved in 5-coordinate bonding with one organic (hydrazone) unit and two labile chloride ligands. The ligand acts as NNO–tridentate donor system. Iron is coordinated to pyridine ring nitrogen, azomethine nitrogen and benzoyl oxygen atoms and the two chloride ligands bind with metal completing distorted square pyramidal structure. The ligands and iron complexes are screened for their anti-bacterial activities against Pseudomonas aureoginos and Bacillus cereus. Among ligands, acetoyl hydrazones show more activity than the corresponding benzoyl hydrazones. The hydrazones having a methyl/ and pyridine groups show higher antibacterial activity. The iron complexes show higher activity than the metal free ligands.

中文翻译：

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官能化配体的铁（III）配合物的合成，光谱研究和抗菌活性：含不稳定配体的新型五坐标配合物的X射线结构测定

具有通式FeLCl _2的铁（III）配合物[其中，L = 2-乙酰基吡啶乙酰hydr（APAH），2-乙酰基吡啶苯甲酰（（APBH），2-乙酰基噻吩乙酰（（ATAH）和2-对乙酰噻吩苯甲酰（（ATBH）]基于摩尔电导率，电子和红外光谱合成和表征。使用单晶X射线晶体学测定具有APBH配体的铁（III）配合物的结构。该复合物在单斜空间群P21 / n中结晶，a = 7.8490（6）Å，b = 15.1018（11）Å，c = 13.2263（10）Å，α= 90°，β= 100.183（3）°，γ= 90°，V = 1543.1（2）埃³Z = 4，中心Fe（III）离子由一个三齿APBH配体配位。铁参与与一个有机（））单元和两个不稳定的氯化物配体的5-配位键合。配体充当NNO-三齿供体系统。铁与吡啶环氮，偶氮甲碱氮和苯甲酰氧原子配位，并且两个氯化物配体与金属结合，完成了扭曲的方形锥体结构。筛选配体和铁配合物对金黄色假单胞菌和蜡状芽孢杆菌的抗菌活性。在配体中，乙酰基比相应的苯甲酰基显示更高的活性。具有甲基和吡啶基的hydr显示较高的抗菌活性。铁络合物显示出比不含金属的配体更高的活性。