Control of Exchange Interactions in π Dimers of 6-Oxophenalenoxyl Neutral π Radicals: Spin-Density Distributions and Multicentered-Two-Electron Bonding Governed by Topological Symmetry and Substitution at the 8-Position
作者:Shinsuke Nishida、Junya Kawai、Miki Moriguchi、Tomohiro Ohba、Naoki Haneda、Kozo Fukui、Akira Fuyuhiro、Daisuke Shiomi、Kazunobu Sato、Takeji Takui、Kazuhiro Nakasuji、Yasushi Morita
DOI:10.1002/chem.201301783
日期:2013.9.2
nyl (TBPLY) radical exists as a π dimer in the crystal form with perfect overlapping of the singly occupied molecular orbitals (SOMOs) causing strong antiferromagnetic exchange interactions. 2,5‐Di‐tert‐butyl‐6‐oxophenalenoxyl (6OPO) is a phenalenyl‐based air‐stable neutral π radical with extensive spin delocalization and is a counter analogue of phenalenyl in terms of the topological symmetry of the
的三-叔-butylphenalenyl(TBPLY)基团存在,如结合的单独完美重叠的晶体形式的π二聚体占据分子轨道(SOMOS)使强反铁磁交换相互作用。2,5-二叔丁基-6-氧代苯甲酰氧基(6OPO)是具有广泛自旋离域作用的基于苯菲烯的空气稳定中性π自由基,就自旋密度分布的拓扑对称性而言,它是与苯菲烯的对映体。X射线晶体结构分析表明,8-叔丁基和8-(p- XC 6 H 4)-6OPOs(X = I,Br)在结晶状态下也形成π二聚体。8- tert的π-二聚体结构-3-丁基-6OPO与TBPLY相似,尽管其SOMO-SOMO重叠比TBPLY小。8-(p- XC 6 H 4)衍生物形成滑动堆积的π二聚体,其中SOMO-SOMO重叠大于8-叔丁基-6OPO,但仍小于TBPLY。6OPO衍生物的固态电子光谱显示弱得多的二聚体内部电荷转移带,以及8-(p- BrC 6 H 4的SQUID测量))