Supramolecular Helical Chirality of Schiff Base Copper(II) Complexes and Their Chiroptical Spectroscopy

本文通过不同的手性二胺(pn = 1,2-丙二胺、chxn = 1,2-环己二胺、dpen =; 1,2-二苯基乙二胺)与脱氢乙酸(dha)缩合,获得了N_2O_2型手性席夫碱配体(dha-en),进而合成了相应的三对手性席夫碱Cu(II)络; 合物([Cu(dha-R/S-pn)](1a和1b)、[Cu(dha-R,R/S,S-chxn)](2a和2b)、[Cu(dha-R,R/S,S; -dpen)](3a和3b),对其进行的固体和溶液电子圆二色(ECD)及溶液振动圆二色(VCD)光谱测试表明,这些化合物在固体和溶液状态下的金属; 中心的主要配位模式和绝对构型基本一致。此外,通过单晶结构分析发现:对于络合物2a/2b以及3a/3b,中心金属Cu(II)除了与手性dha-en; 四齿配位外,还与相邻分子内酯环上的羰基发生弱的轴向配位形成一维超分子螺旋链,即实现了配位键构筑的席夫碱络合物的手性超分子自组装。本文对两对手性络; 合物2a/2b以及3a/3b的手性结构基元及其与超分子螺旋之间的关系进行了讨论。将本文所获实验VCD光谱数据与文献报道的相关数据进行比对分析,可; 以相互印证,并呈现一定的绝对构型关联规律且具有手性配位立体化学结构的指纹特征。Three pairs of N2O2-type Schiff base ligands were synthesized by condensing dehydroacetic acid (dha) with chiral 1,2-diaminopropane (pn), trans-1,2-diaminocyclohexane (chxn), and 1,2-diphenylethylenediamine (dpen). These chiral ligands were used to coordinate copper(II) ions to produce the corresponding Schiff base Cu(II) complexes: [Cu(dha-R/S-pn)] (1a and 1b), [Cu(dha-R,R/S,S-chxn)] (2a and 2b), and [Cu(dha-R,R/S,S-dpen)] (3a and 3b). Detailed analyses using electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) spectroscopies reveal that these Schiff base Cu(II) complexes retain the main coordination modes and the absolute configurations of the metal centers, both in solution and the solid state. In addition, according to the crystal structures, the central Cu(II) ions of 2a/2b and 3a/3b were found to not only coordinate to the chiral dha-en ligands, but were also axially coordinated to the carbonyl groups of the contiguous lactonic rings, providing one-dimensional supramolecular helical chains through self-assembly. In this work, we deeply studied the relationship between the chiral coordination units and the supramolecular helical structures of 2a/2b and 3a/3b. By comparing our experiment VCD spectroscopic data with related VCD spectral features reported in the literature, a specific correlation between the VCD spectral properties and absolute configurations was investigated, which provided fingerprint characteristics for chiral coordination structure.National Natural Science Foundation of China [21273175

Further Understanding on the Measurement Methods for Solid-State Circular Dichroism Spectroscopy——Discussion on Concentration Effects

对近期发展的固体圆二色(Cd)光谱测试方法进行了概述、评价和比较,着重探讨了“浓度效应“的存在使固体Cd光谱失真的原因.通过对本课题组和其他作者已报道的四种化合物的固体Cd谱再测试的反思,强调了依手性化合物的手性光谱学性质不同,根据浓度梯度实验选择其合适测试浓度的必要性.对固有手性的阻转异构化合物(S)-1,1-联二萘酚(S-bInOl)进行了成膜法固体Cd谱浓度梯度测试,发现所得固体薄膜Cd谱中也存在着“浓度效应“.In this paper, the recent developments in measurement methods of solid-state circular dichroism(CD) spectroscopy were summarized and discussed, especially the effects of concentration on solid-state CD spectral distortions.By reinspection and introspection of the solid-state CD spectra of four reported compounds, concentration gradient measurements were proved to be necessary for appropriate concentrations, which are greatly related to the chiroptical properties.The thin film solid- state CD measurements of the inherently chiral atropisomer(S)-1,1'-bi-2-naphthol(S-BINOL) were carried out with concentration gradient measurements.Using this film- state technique for the first time, the results show some subtle correlations between the CD curves and the special concentrations.国家自然科学基金(21273175;21271150;21001026); 中国科学院福建物质结构研究所结构化学国家重点实验室基金(20110006;20130008)资助项目~

Stereochemistry and solid-state circular dichroism spectroscopy of eight-coordinate chiral lanthanide complexes

本文立体选择性地合成了八配位ln(Ⅲ)络合物[Eu(dbM)3lrr](1)、[Eu(dbM)3lSS](2)和[Tb(dbM)3lrr](3)(lrr/lSS=(-)/(+)-4,5-蒎烯基联吡啶,HdbM=二苯甲酰甲烷),利用单晶衍射、uV-VIS和固体Cd光谱对其进行了表征.晶体结构分析和固体Cd光谱表明1和2互为对映体.采用激子手性方法,通过与六配位和七配位的β-二酮络合物的固体Cd光谱的对比,提出含β-二酮的八配位ln(III)络合物的绝对构型关联规则.该系列络合物的畸变四方反棱柱的Δ或Λ绝对构型也被其单晶结构所证实.Eight-coordinate chiral lanthanide complexes [Eu(dbm3LRR](1),[Eu(dbm)3LSS](2) and [Tb(dbm)3LRR](3) (LRR/L SS=(-)/(+)-4,5-pineno-2,2'-bipyridine,Hdbm=dibenzoylmethane) were synthesized stereoselectively,which were characterized by UV-vis,CD spectra and X-ray single-crystal diffraction.The mirror-image structure features of the complexes 1 and 2 were obtained by combination of the solid-state CD spectra and the crystal structure analysis.After further comparison with the solid-state CD spectra of six-coordinate and seven-coordinate metal complexes containing β-diketone ligands,the CD spectra-absolute configuration correlation rule for the eight-coordinate β-diketonate lanthanide complexes was proposed through the exciton chirality method for the first time.The Δ or Λ absolute configurations of the complexes 1～3 with the distorted square antiprism geometry were confirmed by X-ray single-crystal analysis.国家自然科学基金(批准号:20773098;20973136);厦门大学科技创新工程基金(系列2)(批准号:XDKJCX20061027)资

Mirror Symmetry Breaking and Absolute Configuration Correlations of Fe(Ⅲ) Complexes with Achiral Substituted o-Iminobenzosemiquinonato Ligands

以2-苯胺基-4,6-二叔丁基苯酚(H2l) 和 fECl2·4H2O 为原料制备了一对手性半醌 fE(III) 络合物Λ-MEr-[fE(lISQ)3]和Δ-MEr-[fE(lISQ)3] (lISQ: 2-苯亚胺基-4,6-二叔丁基苯酚, MEr : 经式构型), 通过单晶 X 射线衍射分析结合单晶压制片膜的固体圆二色(Cd)光谱确定了该络合物的绝对构型, 在此基础上建立了此类半醌络合物[M(lISQ)3] (M=Cr, fE, CO)的惟手性金属中心绝对构型与固体 Cd 光谱之间的关联. 此外, 还对 10 份合成的[fE(lISQ)3]的大宗产物粉末与单晶的固体 Cd 谱进行了比对分析, 以及对 1 份合成产物进行 10 次重结晶的固体Cd 光谱表征. 研究表明该化合物在结晶过程中发生了镜面对称性破缺 (MSb), 对映体过量 (EE) 值在15%-100%之间.A pair of chiral o-iminobenzosemiquinonato Fe(Ⅲ) complexes, Λ-mer-[Fe(L ISQ ) 3 ] and Δ-mer- [Fe(L ISQ ) 3 ] (L ISQ : 2-phenylimino-4,6-di-tert-butylphenol, mer : meridian configuration), were synthesized from 2-anilino-4,6-di-tert-butylphenol (H 2 L) and FeCl 2 · 4H 2 O.Their absolute configurations were determined by single crystal X-ray diffraction (XRD) and solid-state circular dichroism (CD) spectra (the same single crystal for XRD was dispersed in KCl).Correlations between the absolute configurations of the chiral-at- metal o-iminobenzosemiquinonato M(Ⅲ) complexes [M(L ISQ ) 3 ] (M=Cr, Fe, Co) and their solid-state CD spectra were also established.Comparison between solid-state CD spectra of the bulk samples from 10 different syntheses and their single crystals were thoroughly analyzed.The solid-state CD spectra of the powdered samples from 10 different crystallizations of one product were characterized.These studies indicated that mirror symmetry breaking (MSB) occurred during the crystallization process of the Fe(Ⅲ) complexes and their enantiomeric excess (ee) values were between 15% and 100%.国家自然科学基金(21273175;20973136)资助项目~

中亚增生造山演化与成矿预测应用研究

本成果结合中亚增生造山带的基本特征,以解剖增生楔的组成、构造样式和时代及其时空分布规律为切入点,在全球最大的增生造山带的一些关键薄弱环节进行构造解析和年代学分析,全面理解增生造山作用和其所蕴含的大陆动力学意义,建立中亚成矿域的大陆动力学与成矿系统演化模型,在此基础上开展大型矿集区预测,建立大型矿集区预测的理论和方法技术平台,为中亚成矿域找矿工作提供理论基础和技术支撑。 本成果主要创新点： (1)通过对增生楔岩石的物质成分分析,岩石组合分析以及高精度的地质年代学测试阐明其大地构造背景和演化历史,从空间和时间两个方面构建了大陆边缘增生构造带的精细结构,集约古生代的俯冲增生过程与..

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^