TY - JOUR
T1 - Toward a Charged Homo[2]catenane Employing Diazaperopyrenium Homophilic Recognition
AU - Gong, Xirui
AU - Zhou, Jiawang
AU - Hartlieb, Karel J.
AU - Miller, Claire
AU - Li, Peng
AU - Farha, Omar K.
AU - Hupp, Joseph T.
AU - Young, Ryan M.
AU - Wasielewski, Michael R.
AU - Stoddart, J. Fraser
PY - 2018/5/30
Y1 - 2018/5/30
N2 - An octacationic diazaperopyrenium (DAPP2+)-based homo[2]catenane (DAPPHC8+), wherein no fewer than eight positive charges are associated within a mechanically interlocked molecule, has been produced in 30% yield under ambient conditions as a result of favorable homophilic interactions, reflecting a delicate balance between strong π- π interactions and the destabilizing penalty arising from Coulombic repulsions between DAPP2+ units. This DAPPHC8+ catenane is composed of two identical mechanically interlocked tetracationic cyclophanes, namely DAPPBox4+, each of which contains one DAPP2+ unit and one extended viologen (ExBIPY2+) unit, linked together by two p-xylylene bridges. The solid-state structure of the homo[2]catenane demonstrates how homophilic interactions play an important role in the formation of DAPPHC8+, in which the mean ring planes of the two DAPPBox4+ cyclophanes are oriented at about 60° with respect to each other, with a centroid-to-centroid separation of 3.7 Å between the mean planes of the outer ExBIPY2+ and inner DAPP2+ units, and 3.6 Å between the mean planes of the two inner DAPP2+ units. We show that irradiation of the DAPPHC8+ catenane at 330 nm in acetonitrile solution results in simultaneous energy and electron transfer. The latter occurs from the inner DAPP2+ dimer to the outer ExBIPY2+ unit, leading to the generation of a temporary charge-separated state within a rigid and robust homo[2]catenane. Compared to DAPPBox4+, both forward- and back-electron transfer in DAPPHC8+ occur with faster rates, owing to the closer proximity between the electron donor and acceptor in the homo[2]catenane than in the separated cyclophane.
AB - An octacationic diazaperopyrenium (DAPP2+)-based homo[2]catenane (DAPPHC8+), wherein no fewer than eight positive charges are associated within a mechanically interlocked molecule, has been produced in 30% yield under ambient conditions as a result of favorable homophilic interactions, reflecting a delicate balance between strong π- π interactions and the destabilizing penalty arising from Coulombic repulsions between DAPP2+ units. This DAPPHC8+ catenane is composed of two identical mechanically interlocked tetracationic cyclophanes, namely DAPPBox4+, each of which contains one DAPP2+ unit and one extended viologen (ExBIPY2+) unit, linked together by two p-xylylene bridges. The solid-state structure of the homo[2]catenane demonstrates how homophilic interactions play an important role in the formation of DAPPHC8+, in which the mean ring planes of the two DAPPBox4+ cyclophanes are oriented at about 60° with respect to each other, with a centroid-to-centroid separation of 3.7 Å between the mean planes of the outer ExBIPY2+ and inner DAPP2+ units, and 3.6 Å between the mean planes of the two inner DAPP2+ units. We show that irradiation of the DAPPHC8+ catenane at 330 nm in acetonitrile solution results in simultaneous energy and electron transfer. The latter occurs from the inner DAPP2+ dimer to the outer ExBIPY2+ unit, leading to the generation of a temporary charge-separated state within a rigid and robust homo[2]catenane. Compared to DAPPBox4+, both forward- and back-electron transfer in DAPPHC8+ occur with faster rates, owing to the closer proximity between the electron donor and acceptor in the homo[2]catenane than in the separated cyclophane.
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U2 - 10.1021/jacs.8b03407
DO - 10.1021/jacs.8b03407
M3 - Article
C2 - 29723466
AN - SCOPUS:85046633290
VL - 140
SP - 6540
EP - 6544
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 21
ER -