59Co NMR, a facile tool to demonstrate EEE, EEZ, EZZ and ZZZ configurational isomerism in fac-[Co(L-κS,O)3] complexes derived from asymmetrically substituted N,N-dialkyl-N′-aroylthioureas
作者:Ilse Barnard、Klaus R Koch
DOI:10.1016/j.ica.2019.119019
日期:2019.9
which to study fac-[Co(Ln-κS,O)3] complexes in solution. The formation of the previously unrecognized four possible EEE, EZZ, ZZZ and EEZ configurational isomers of fac-[Co(L6-10-κS,O)3] complexes, derived from asymmetrical N,N-dialkyl-N′-acyl(aroyl)thioureas, is easily demonstrated by 59Co NMR. All analytically pure fac-[Co(L6-10-κS,O)3] complexes are in fact mixtures of fac-EEE,EEZ,EZZ,ZZZ-[Co(L6-10-κS
摘要从对称(RC(O)-NH–C(S)NR1R2; R = C6H5,R1,R2 = CH2CH3,(HL,n = 1-5))和不对称的N,N-二烷基-N'-酰基(芳酰基)硫脲(RC(O)-NH-C(S)NR1R2; R = C6H5或C(CH3)3,且R1≠R2 ,(HL,n = 6-10))在溶液中通过1H,13C和59Co NMR进行了研究。59Co核素(I = 7/2)的高接受度及其大的化学位移范围对配体结构,溶剂组成和温度非常敏感。相对较窄的59Co NMR峰和温度系数在+2.16和+3.0 ppm K-1范围内,使59Co NMR成为研究溶液中fac- [Co(Ln-κS,O)3]配合物的有用探针。源自非对称N的fac- [Co(L6-10-κS,O)3]配合物的先前未被识别的四种可能的EEE,EZZ,ZZZ和EEZ构型异构体的形成,N-二烷基-N'-酰基(芳酰基)硫脲容易通过59Co