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Preparation and Properties of Organic Chalcogen Compounds Bearing Long-chain Bonds Constructed by more than four Chalcogen Atoms

四个以上硫族原子构成的长链有机硫族化合物的制备及性能

基本信息

批准号：
09640635
负责人：
NAKANISHI Waro
金额：
$ 1.86万
依托单位：
Wakayama University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

The structures of 1-[8-(p-YCィイD26ィエD2HィイD24ィエD2Se)CィイD210ィエD2HィイD26ィエD2]SeSe[CィイD210ィエD2HィイD26ィエD2(SeCィイD26ィエD2HィイD24ィエD2Y-p]-8']-1' (1a(Y = H)) and 1-(MeSe)-8-(p-YCィイD26ィエD2HィイD24ィエD2Se)CィイD210ィエD2HィイD26ィエD2 (2a(Y = H), 2b(Y = OMe), and 2d(Y = Cl)) are determined by the X-ray crystallographic analysis. Those of 1a, 2a, 2b, and 2d are double type A-type B pairing, type C-type C pairing, pseudo-type A-type B pairing, and pure type A-type B pairing, respectively. The structure is type A if the Se-C bond being almost perpendicular to the naphthyl plane, type B when the Se-C bond being placed on the plane, or type C for the intermediate between type A and type B. Double type A-type B pairing in 1a is characterized by the four center-six electron bond (4c-6e) and type A-type B pairing in 2b and 2d by 3c-4e. Type C-type C pairing in 2a is analyzed by the distorted nonbonded π-type 2c-4e interaction, which avoid severe exchange repulsion due to the nonbonded π-type 2c-4e interaction.The ィイD177ィエD1Se NMR chemical shifts (δ(Se)) of 1a-1g (Y = H, OMe, Me, Cl. Br, COOEt, NOィイD22ィエD2 for a-g, respectively) are measured, together with those of 2a-2g. While the plot of δ(Se) at 8-positions versus those at 1-positions gives a negative proportionality constant of -0.282 for 1 (inverse correlation), the value is positive for 2 (0.252 : regular correlation). The inverse correlation must be the results of the four center-six electron bond constructed by the four Se atoms aligned linearly in 1. The regular correlation is expected for the 2c-4e with some contribution of the through-bond mechanism via the naphthalene π-system. In order to clarify the mechanism for the correlations, ab initio MO calculations, containing δ(Se) based on the GIAO theory, are performed on the models of 1 and 2. The results exhibit the important role of the 4c-6e for the inverse correlation in 1.

1-[8-(p-YCィイD26ィエD2HィイD24ィエD2Se)CィイD210ィエD2HィイD26ィエD2]SeSe[CィイD210ィエD2HィイD26ィエD2(SeCィイD26ィエD2HィイD24ィエD2Y-p]-8‘]-1’(1a(Y=H))和1-(MeSe)-8-(p-YCィイD26ィエD2HィイD24ィエD2Se)CィイD210ィエD2H的结构ィイD26ィエD2(2a(Y=H)，2b(Y=OMe)和2d(Y=Cl))。1a、2a、2b和2d的配对分别为双A-B配对、C-C类型配对、伪A-B配对和纯A-B配对。如果Se-C键几乎垂直于萘基平面，则结构为A型，当Se-C键放置在平面上时为B型，或为A型和B型之间的中间体的C型。1a中的双型A-B型配对的特征是四个中心-六电子键(4c-6e)和2b和2d中的A型-B型配对3c-4e。用扭曲的非键π2c-4e相互作用分析了2a中的C-C型配对，避免了非键π-2c-4e相互作用引起的严重交换排斥.ィイD177ィエD1Se核磁共振化学位移(δ(Se))为1a-1g(Y=H，OMe，Me，Cl.BR，COOET，NOィイD22ィエD2分别为a-g)，以及2a-2g的。虽然8个位置的δ(Se)与1个位置的Se的曲线图给出了1的负比例常数-0.282(负相关)，但2的值是正的(0.252：规则相关)。逆关联一定是4个Se原子在1中线性排列形成的4个中心-6电子键的结果。对于2c-4e原子，规则关联可能是通过萘的π-体系的通键机制做出的贡献。为了阐明关联的机制，基于GIAO理论，对模型1和模型2进行了含δ(Se)的从头算分子轨道计算。结果表明，4c-6e对1的反关联起着重要的作用。