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enantiomeric excess 1

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porphyrin dimer 1

pulse plasma chemical vapor deposition 1

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Improvement in growth yield of single-walled carbon nanotubes with narrow chirality distribution by pulse

Bin Xu, Toshiro Kaneko, Toshiaki Kato

Frontiers of Chemical Science and Engineering 2019, Volume 13, Issue 3, Pages 485-492 doi: 10.1007/s11705-019-1831-2

Abstract: was developed for improving the growth yield of single-walled carbon nanotubes (SWNTs) with a narrow chiralitycould be improved by repetitive short duration pulse plasma CVD, while maintaining the initial narrow chiralityThe growth of SWNTs with a narrow chirality distribution could be controlled by the difference in the

Keywords： single-walled carbon nanotubes chirality-controlled synthesis pulse plasma chemical vapor deposition

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Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

Daniel T. Payne, Mandeep K. Chahal, Václav Březina, Whitney A. Webre, Katsuhiko Ariga, Francis D’Souza, Jan Labuta, Jonathan P. Hill

Frontiers of Chemical Science and Engineering 2020, Volume 14, Issue 1, Pages 28-40 doi: 10.1007/s11705-019-1869-1

Abstract: Chiral 1,1’-binaphthyl-linked diporphyrin ‘tweezers’ ( )- /( )- and the corresponding zinc(II) complexes ( )- /( )- were prepared as chiral host molecules, and their utility for chiral analyses (especially enantiomeric excess ( ) determinations) were evaluated. Tris(1- -dodecyl)porphyrins were used for the first time as the interacting units. Host capabilities of the diporphyrin tweezers were investigated by titrations with ( , )- and ( , )-cyclohexane-1,2-diamine (CHDA). The host molecules could be used as multichannel probes of by using UV-vis, circular dichroism (CD), fluorescence emission and H nuclear magnetic resonance ( H-NMR) methods. Chiral configurations could also be differentiated using CD or H-NMR spectroscopy. All three optical techniques give good resolution of with reasonable sensitivity considering the low concentrations used (ca. 10 mol·L ). The determination of CHDA enantiomers using NMR spectroscopy is also possible because of the reasonably well separated resonances in the case of ( , )- and ( , )-CHDA. Non-metallated ( )- /( )- hosts could not be used to detect chiral information in a strongly acidic chiral guest. This work demonstrates the utility of 1,1’-binapthyl-linked chiral hosts for chiral analysis of ditopically interacting enantiomers.

Keywords： porphyrin dimer chirality enantiomeric excess CD fluorescence