The synthesis and crystallization of two verdazyl radicals, 1,5‐dimethyl‐3‐(4′‐carboxyphenyl)‐6‐oxoverdazyl HIMe and 1,5‐diisopropyl‐3‐(4′‐carboxyphenyl)‐6‐oxoverdazyl HIiPr, are described. The electrochemical studies revea...
http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
https://www.riss.kr/link?id=O119034533
2018년
-
1434-1948
1099-0682
SCI;SCIE;SCOPUS
학술저널
517-524 [※수록면이 p5 이하이면, Review, Columns, Editor's Note, Abstract 등일 경우가 있습니다.]
0
상세조회0
다운로드다국어 초록 (Multilingual Abstract)
The synthesis and crystallization of two verdazyl radicals, 1,5‐dimethyl‐3‐(4′‐carboxyphenyl)‐6‐oxoverdazyl HIMe and 1,5‐diisopropyl‐3‐(4′‐carboxyphenyl)‐6‐oxoverdazyl HIiPr, are described. The electrochemical studies revea...
The synthesis and crystallization of two verdazyl radicals, 1,5‐dimethyl‐3‐(4′‐carboxyphenyl)‐6‐oxoverdazyl HIMe and 1,5‐diisopropyl‐3‐(4′‐carboxyphenyl)‐6‐oxoverdazyl HIiPr, are described. The electrochemical studies reveal that the oxidation of the two radicals is reversible, whereas their reduction is irreversible. The EPR spectrum of both radicals essentially exhibits a nine‐line pattern related to the mean hyperfine interaction of the unpaired electron with the nitrogen atoms of the verdazyl cycle. The single‐crystal X‐ray diffraction of the intermediates towards HIiPr allows a fine description of the cyanoborane adduct, which is the key intermediate of this synthesis. The verdazyl radicals themselves are obtained as single crystals. In the case of HIiPr, depending on the solvent, two polymorphs are crystallized. The structure resolution reveals that, in the solid state, the organization of the verdazyl radicals is governed by both H‐bonding and π–π interactions and is reminiscent of the H‐bonded structures that can be present in solution. Within the 1D π stacks observed in the three compounds, the verdazyl–verdazyl distance varies from 4.88 Å in HIMe to 7.90 Å in HaIiPr. This modulation of the distance strongly influences the antiferromagnetic intermolecular exchange interaction between π‐stacked radicals, which goes from J = –90 cm–1 (H = –JΣSiSi+1) for HIMe to –12.96(3) cm–1 for HbIiPr and –0.92 cm–1 for HaIiPr.
Two new stable verdazyl radicals were synthesized. In the solid state, they are organized as one‐dimensional π stacks. The overlap between the SOMO leads to an antiferromagnetic exchange interaction governed by the verdazyl–verdazyl distance.