Organicbiradicalcompounds having a biphenyl or naphthalene core and long alkyl groups with TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) radicals at their ends were found to show moderately strong antiferromagnetic interactions, being based on the singlet-triplet model. The behavior could be understood by considering the structures as being assembled in a "hand-in-hand" fashion.
Azobenzene Derivatives Carrying a Nitroxide Radical
作者:Shin'ichi Nakatsuji、Masahiro Fujino、Satoko Hasegawa、Hiroki Akutsu、Jun-ichi Yamada、Vladimir S. Gurman、Andrey Kh.Vorobiev*
DOI:10.1021/jo062266f
日期:2007.3.1
Several trans-azobenzene derivatives carrying a nitroxide (aminoxyl) radical (2a, 6a-12a) were prepared, and their photoisomerization reactions to the corresponding cis-isomers were investigated. Although no fruitful results could be obtained for the photoisomerizations of the derivatives with para-subsituents (9a-12a), the unsubstututed derivatives at the para-position (2a, 6a, 7a, 8a) were found to show photoisomerizations by irradiation to give the corresponding cis-isomers (2b, 6b, 7b, 8b), being isolated as relatively stable solid materials, and the change of the intermolecular magnetic interactions was apparently observed by the structural change for each photochromic couple.