Determination of Ground State Spin Multiplicity of Basic non-Kekule Hydrocarbons by Measuring Paramagnetic Susceptibility.

通过测量顺磁化率测定碱性非凯库勒烃的基态自旋多重度。

• 批准号: 06453035
• 负责人: IWAMURA Hiizu
• 金额: $ 4.48万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06453035/
• 关键词: diradical; non-Kekule molecules; tetramethleneethane; matrix isolation; triplet ground state

2,3-Dimethylenecyclohexa-1,4-diyl (1) is a disjoint diradical and the ground-state multiplicity is still in controversy. By means of ESR spectroscopy and magnetic measurement, the ground-state multiplicity of the title compound was studied. From orthophtalic acid, 5,6-dimethylene-2,3-diazabicyclo[2,2,2, ]oct-2-ene was synthesized according to the method of W.R.Roth. The photolysis was carried out in MTHF matrix by using light from high-pressure mercury lamp to give 1. The photoproduct depended on the wavelenght of irradiation. The light of 312.6 nm gave the target molecule and the light of 302.2 nm gave another product. The magnetic property of 1 was investigated by means of direct measurement of the magnetization. It was found that the singlet and triplet state of 1 was almost degenerate. This result is a crucial determination of the problem where there has been a long controversy between theory and experiment.

2,3-二亚甲基环己-1,4-二基 (1) 是一个不相交的双自由基，其基态多重性仍存在争议。通过ESR光谱和磁测量，研究了标题化合物的基态多重性。根据W.R.Roth的方法，由邻苯二甲酸合成5,6-二亚甲基-2,3-二氮杂双环[2,2,2,]辛-2-烯。利用高压汞灯的光在MTHF基质中进行光解，得到1。光产物取决于照射的波长。 312.6 nm 的光产生目标分子，302.2 nm 的光产生另一种产物。通过直接测量磁化强度来研究1的磁性。发现1的单重态和三重态几乎是简并态。这一结果对于理论与实验之间长期存在争议的问题具有决定性意义。

项目成果

K. Matsuda: "Effect of the Oxidation State of the Sulfur Atom on the Exchange Interaction between Two Triplet Carbene Units through Diphenyl Sulfide p, p′-Diyl Couplers" Chem. Lett.1995. 1085-1086 (1995)

K. Matsuda：“硫原子的氧化态对通过二苯硫醚对，对-二基偶联剂之间的两个三线态卡宾单元之间的交换相互作用的影响”Chem.1995。

K. Matsuda: "Design,Synthesis,and Characterization of Three Kinds of π-Cross-Conjugated Hexacarbenes with High-Spin(S=6)Ground States"" J. Am. Chem. Soc.117. 5550-5560 (1995)

K. Matsuda：“具有高自旋 (S=6) 基态的三种 π-交叉共轭六碳烯的设计、合成和表征”J. Am. Chem. Soc.117. 5550-5560 (1995)

D. C. Oniciu: "Synthesis and ESR Characterization of Triphenylmethane Derivatives Carrying N-tert-Butyl Nitroxide Radical Moieties: Use of the Diradical as a Ligand for a Complex with Mn(II)(hfac_2)" J. Chem. Soc. Perkin Trans. 2. (in press). (1996)

D. C. Oniciu：“携带 N-叔丁基氮氧自由基部分的三苯甲烷衍生物的合成和 ESR 表征：使用双自由基作为与 Mn(II)(hfac_2) 配合物的配体”J. Chem。

Masaki Noro: "Carbene-Carbene Interconversion between 1-and 3-Phenyl-2-propynylidenes" J.Am.Chem.Soc.116. 6179-6190 (1994)

Masaki Noro：“1-和 3-Phenyl-2-propynylidenes 之间的卡宾-卡宾互变”J.Am.Chem.Soc.116。

Daniela C.Oniciu, K.Matsuda, and H.Iwamura: "Synthesis and EPR Characterisation of Triphenylmethane Derivatives Carrying N-tert-Butyl Nitroxide Radical Moieties : Use of the Diradicalas a Ligand for a Complex with Mnll (hfac)_2." J.Chem.Soc., Perkin 2.199

Daniela C.Oniciu、K.Matsuda 和 H.Iwamura：“携带 N-叔丁基氮氧自由基部分的三苯甲烷衍生物的合成和 EPR 表征：使用 Diradicalas 作为与 Mnll (hfac)_2 配合物的配体。”