Effects of Halo-Substitution on 2′-Chloro-5′-halo-phenyl-1,2,3,5-dithiadiazolyl Radicals: A Crystallographic, Magnetic, and Electron Paramagnetic Resonance Case Study
作者:Christos P. Constantinides、Emma Carter、Dana Eisler、Yassine Beldjoudi、Damien M. Murphy、Jeremy M. Rawson
DOI:10.1021/acs.cgd.6b01700
日期:2017.6.7
magnetometry and X-band continuous-wave electron paramagnetic resonance studies revealed the presence of a thermally accessible triplet state in all cases, with the singlet–triplet separation appearing in the order 1 > 2 > 3 > 4, consistent with a reduction in the overlap integral with increasing intradimer S···S separation. Variable temperature structural studies on both 2 and 4 reveal a structural evolution
芳基取代的二噻二唑2'-Cl-5'-XC 6 H 3 CNSSN • [ 1(X = F),2(X = Cl),3(X = Br),4(X = I)]进行说明。在所有四种情况下,基团都采用扭曲的π*-π*二聚体堆叠,且堆叠之间存在S···X接触。在1(单斜P 2 / C ^)s ...氯触点通过一个noncrystallographic 3倍轴形成超分子的三聚体表现,而堆间小号... X在触点2(三斜晶P 1),3和4(形成同构对,正交Pna 2 1)形成超分子链。尽管所有结构都采用π*-π*顺式二聚体基序,但调节卤素会改变二聚体的S···S距离。可变温度SQUID磁力测定法和X波段连续波电子顺磁共振研究表明,在所有情况下均存在热可及的三重态,单重态-三重态分离的出现顺序为1 > 2 > 3 > 4,与还原一致随着重叠二聚体S···S分离的增加,分子的重合度增加。2和4的可变温度结构研究揭