Extension of Azine-Triazole Synthesis to Azole-Triazoles Reduces Ligand Field, Leading to Spin Crossover in Tris-L Fe(II)
作者:Sandhya Singh、Sally Brooker
DOI:10.1021/acs.inorgchem.9b02993
日期:2020.1.21
general synthesis used to access many examples of azine-triazoles. The tris-L FeIIcomplexes of the azine-triazoles are consistently low spin (LS). As intended, these new azole-triazole ligands provide lower field strengths, resulting in high-spin (HS) [FeII(L4NMeIm)3](BF4)2 (1·4H2O) and spin crossover (SCO) active [FeII(L4SIm)3](BF4)2 (2·0.5H2O). Single-crystal structure determinations revealed that
唑-三唑大鼠配体的第一个例子是双齿L4NMeIm(3-(1-甲基-1H-咪唑-4-基)-5-苯基-4-(对甲苯基)-4H-1,2,4-三唑)和L4SIm(4-(5-苯基-4-(对甲苯基)-4H-1,2,4-三唑-3-基)噻唑)已经制备,通过扩展通用的合成方法获得了许多嗪-三唑的实例。嗪-三唑的tris-L FeII配合物始终是低自旋(LS)。如预期的那样,这些新的唑-三唑配体提供较低的场强,从而产生高旋转(HS)[FeII(L4NMeIm)3](BF4)2(1·4H2O)和自旋交联(SCO)活性[FeII(L4SIm) 3](BF4)2(2·0.5H2O)。单晶结构测定表明,在100 K下1·溶剂为HS,而2·溶剂为LS。空气干燥晶体的固态可变温度磁研究表明,甲基咪唑-三唑复合物1·4H2O保持HS,而噻唑-三唑复合物2·0.5H2O经历两步逐步SCO(T1 / 2约为275和350 K