J.m.chem.soc.2001,12312232-12237 Photochromic Atropisomer Generation and Conformation Determination in a Ruthenium Bis(bipyridine)Phosphonite y-Cyclodextrin System Dusan Hesek,' Guy A. Hembury, Michael G. B. Drew, Victor V. Borovkov,' and Yoshihisa Inoue*, Contribution from the Inoue Photochirogenesis Project, ERATO. Japan Science and Technology The University of Reading, Whiteknights, Reading RG6 6AD, U.K Received July 2, 2001 Abstract:Irradia Php(ome))(ci)cl(2)ata>460 nm results in the photochromic the PhP(OMe) moiety around the racemization, it was found that ilitated the stabilization circular dichroism spectrum ism spectrum, as a ety(the active further detected by ersion could be ion of the conformation of the new atropison ar dichroism spectra by exciton coupling the Scheme CI OCH OCH3 ,He Reagents and conditions: () PhP(OMe), MeOH, reflux. Scheme 2. Schematic Representation of the Proposed Photochromic Generation of the New Atropisomer of 2 ⊕ OCH3 hv 460 nm CH, XCD OCH3 OCH3
(a)Ground sure aroo somer 间时 Gcaindsta+ ngn enegy slat aIoouomer amodal fc)Ho energy wa'e topomer 10 -20 Figure 4. The CD spectra of 2+y-CDx, before and after irradiation