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Schuster, Gary B. Zhang, Yifan 2011-05-07T13:51:06Z 2011-05-07T13:51:06Z 10000-01-01 1995 Compounds with potential applications as phototriggers for a chiroptical liquid crystal switch were investigated via several approaches. Chiral exciton coupling theory was first used to design and synthesize a series of axially chiral arylmethylene cyclohexanes in both racemic and optically active forms for use as potential photoresolvable mesogens. It was found that these compounds have two spectrally overlapping chromophores which lead to enhanced circular dichroism. With appropriate substituents, some of them form liquid crystal phases. The photochemical and chiroptical properties of these compounds were studied to assess their suitability as phototriggers. It was found that the Kuhn anisotropy factor (g$\sb\lambda$) of these compound is too small for this application. By incorporating chromophores with electronic forbidden transitions (n$\pi\sp*$) into the design, two chiral bicyclo ketones, 3-phenylmethylenebicyclo (3.2.1) octane-8-one and 8-phenylmenthylenebicyclo (3.2.1) octan-3-one, were synthesized in racemic and optically active forms. Preliminary studies have shown the 8-phenylmethylenebicyclo (3.2.1) octan-3-one is the first photoresolvable bichromophoric molecule with a g$\sb\lambda$ value of 0.051. However, the low solubility of this compound in some nematic liquid crystals make it unsuitable for use as a liquid crystal based phototrigger. Made available in DSpace on 2011-05-07T13:51:06Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9624548.pdf: 4616182 bytes, checksum: 3ddc491f51d5f63d1c384dbe94c03d14 (MD5) Previous issue date: 1995 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:59:54Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:28:18-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9624548 (UMI)AAI9624548 http://hdl.handle.net/2142/22775 eng Copyright 1995 Zhang, Yifan Chemistry, Organic Design and synthesis of suitable phototriggers for a chiroptical liquid crystal switch text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.