Synthesis and ferroelectric properties of platinum(II) complexes with chiral isoxazoline ligand

• DOI: 10.1016/j.poly.2013.05.024
• Publication Date: 2013-05-23T04:05:06Z
• Authors: Xiao-Peng Zhang; Jian Liu; Jing-Xuan Zhang; Jia-Hao Huang; Cheng-Zhang Wan; Cheng-Hui Li; Xiao-Zeng You
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract Four chiral square-planar (SP-4) alkynylplatinum(II) complexes Pt(L)(C C–Ph) ( 1 ), Pt(L)(C C–Ph–Br) ( 2 ), Pt(L)(C C–Ph–CH 3 ) ( 3 ) and Pt(L)(C C–Ph–OCH 3 ) ( 4 ) (L = (1S,5S)-6,6-dimethyl-3′-(pyridin-2-yl)-4′H-spiro[bicyclo[3.1.1]heptane-2,5′-isoxazole]) were prepared by the complexation of ligand L with K 2 PtCl 4 and subsequent treatment with corresponding alkynes. Their structures were characterized by single crystal X-ray diffraction and electronic circular dichroism (CD) spectra. Although there are little differences in the molecular structures, these complexes exhibit significantly different molecular packing modes in their crystal structures. Moreover, complexes 1 and 4 crystallize in the polar space group P 2 1 , while complexes 2 and 3 crystallize in the nonpolar space groups ( I 222 for 2 and P 2 1 2 1 2 1 for 3 , respectively). Consequently, complexes 1 and 4 show distinct ferroelectric behaviors and nonlinear optical properties. To the best of our knowledge, our study represents the first example of chiral platinum(II) complexes demonstrating ferroelectric properties.