Stereochemistry controlled by an asymmetric sulfur atom, and a rare example of a kryptoracemate
作者:Imenne Bouamaied、Edwin C. Constable、Catherine E. Housecroft、Markus Neuburger、Jennifer A. Zampese
DOI:10.1039/c2dt30892d
日期:——
close to the asymmetric sulfur atom. A single crystal X-ray diffraction study of 2[Ir(ppy)2(3)][PF6]}·CHCl3·3H2O reveals that the complex crystallizes in the chiral space group P212121, the asymmetric unit containing crystallographically independent Δ- and Λ-[Ir(ppy)2(3)]+ cations. This provides a rare example of a so-called kryptoracemate in the solid state. In MeCN solution, [Ir(ppy)2(1)][PF6], [Ir(ppy)2(2)][PF6]
配位体4-甲硫基-6-苯基-2,2'-联吡啶(1)和相应的亚砜(2)和砜(3)已在溶液中合成,并通过单晶X射线表征为固态衍射。化合物2和3在相同的空间群(C 2 / c)中具有相似的晶胞参数结晶;晶胞体积的小幅增加允许在3中存在额外的氧原子。亚砜和砜基团采用允许分子内O = HC芳基氢键的构象。配合物[Ir(ppy)2 L] [PF 6 ]与L =1,2或3已经制备和表征。配体2中的不对称硫原子产生了该络合物的非对映异构体对,其可以在1 H和13 C NMR光谱中区分。在溶液中,通过[Δ-TRISPHAT] -交换[PF 6 ] -产生了四个非对映异构体,并且我们观察到1 H NMR共振的良好分散,尤其是对于那些分配给接近不对称硫原子的质子的共振。2 [Ir(ppy)2(3)] [PF 6 ]}·CHCl 3 ·3H的单晶X射线衍射研究2 O揭示该络合物在手性空间群P 2 1 2 1 2