Fluorenyl Based Macrocyclic Polyradicaloids

Xuefeng Lu, Sangsu Lee, Yongseok Hong, Hoa Phan, Tullimilli Y. Gopalakrishna, Tun Seng Herng, Takayuki Tanaka, María Eugenia Sandoval-Salinas, Wangdong Zeng, Jun Ding, David Casanova, Atsuhiro Osuka, Dongho Kim, Jishan Wu

Research output: Contribution to journalArticle

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Abstract

Synthesis of stable open-shell polyradicaloids including control of intramolecular spin-spin interactions is a challenging topic in organic chemistry and materials science. Herein, we report the synthesis and physical characterization of two series of fluorenyl based macrocyclic polyradicaloids. In one series (FR-MCn, n = 4-6), the fluorenyl radicals are directly linked at 3,6-positions; whereas in the other series (MC-FnAn, n = 3-5), an additional ethynylene moiety is inserted between the neighboring fluorenyl units. To access stable macrocyclic polyradicaloids, three synthetic methods were developed. All of these stable macrocycles can be purified by normal silica gel column chromatography under ambient conditions. In all cases, moderate polyradical characters were calculated by restricted active space spin-flip method due to the moderate intramolecular antiferromagnetic spin-spin interactions. The excitation energies from the low-spin ground state to the lowest high-spin excited state were evaluated by superconducting quantum interference device measurements. Their physical properties were also compared with the respective linear fluorenyl radical oligomers (FR-n, n = 3-6). It is found that the geometry, i.e., the distortional angle and spacer (w or w/o ethynylene) between the neighboring fluorenyl units, has significant effect on their polyradical character, excitation energy, one-photon absorption, two-photon absorption and electrochemical properties. In addition, the macrocyclic tetramers FR-MC4 and MC-F4A4 showed global antiaromatic character due to cyclic I-conjugation with 36 and 44 I-electrons, respectively.

Original languageEnglish
Pages (from-to)13173-13183
Number of pages11
JournalJournal of the American Chemical Society
Volume139
Issue number37
DOIs
Publication statusPublished - 2017 Jan 1

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Excitation energy
Photons
Organic Chemistry
Column chromatography
SQUIDs
Silica Gel
Silica gel
Materials science
Electrochemical properties
Oligomers
Excited states
Ground state
Gel Chromatography
Physical properties
Electrons
Equipment and Supplies
Geometry

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Cite this

Lu, X., Lee, S., Hong, Y., Phan, H., Gopalakrishna, T. Y., Herng, T. S., ... Wu, J. (2017). Fluorenyl Based Macrocyclic Polyradicaloids. Journal of the American Chemical Society, 139(37), 13173-13183. https://doi.org/10.1021/jacs.7b07335
Lu, Xuefeng ; Lee, Sangsu ; Hong, Yongseok ; Phan, Hoa ; Gopalakrishna, Tullimilli Y. ; Herng, Tun Seng ; Tanaka, Takayuki ; Sandoval-Salinas, María Eugenia ; Zeng, Wangdong ; Ding, Jun ; Casanova, David ; Osuka, Atsuhiro ; Kim, Dongho ; Wu, Jishan. / Fluorenyl Based Macrocyclic Polyradicaloids. In: Journal of the American Chemical Society. 2017 ; Vol. 139, No. 37. pp. 13173-13183.
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Lu, X, Lee, S, Hong, Y, Phan, H, Gopalakrishna, TY, Herng, TS, Tanaka, T, Sandoval-Salinas, ME, Zeng, W, Ding, J, Casanova, D, Osuka, A, Kim, D & Wu, J 2017, 'Fluorenyl Based Macrocyclic Polyradicaloids', Journal of the American Chemical Society, vol. 139, no. 37, pp. 13173-13183. https://doi.org/10.1021/jacs.7b07335

Fluorenyl Based Macrocyclic Polyradicaloids. / Lu, Xuefeng; Lee, Sangsu; Hong, Yongseok; Phan, Hoa; Gopalakrishna, Tullimilli Y.; Herng, Tun Seng; Tanaka, Takayuki; Sandoval-Salinas, María Eugenia; Zeng, Wangdong; Ding, Jun; Casanova, David; Osuka, Atsuhiro; Kim, Dongho; Wu, Jishan.

In: Journal of the American Chemical Society, Vol. 139, No. 37, 01.01.2017, p. 13173-13183.

Research output: Contribution to journalArticle

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AU - Lu, Xuefeng

AU - Lee, Sangsu

AU - Hong, Yongseok

AU - Phan, Hoa

AU - Gopalakrishna, Tullimilli Y.

AU - Herng, Tun Seng

AU - Tanaka, Takayuki

AU - Sandoval-Salinas, María Eugenia

AU - Zeng, Wangdong

AU - Ding, Jun

AU - Casanova, David

AU - Osuka, Atsuhiro

AU - Kim, Dongho

AU - Wu, Jishan

PY - 2017/1/1

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Lu X, Lee S, Hong Y, Phan H, Gopalakrishna TY, Herng TS et al. Fluorenyl Based Macrocyclic Polyradicaloids. Journal of the American Chemical Society. 2017 Jan 1;139(37):13173-13183. https://doi.org/10.1021/jacs.7b07335