Photo‐Cross‐Linking of Polymethacrylates with Stilbene Chromophores in the Side Chains |
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| Authors: | Angelika Jahnke Bernhard Beile Herbert Meier |
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| Institution: | 1. Institute of Organic Chemistry, University of Mainz, Duesbergweg 10?–?14, D‐55099 Mainz, (phone: +49‐6131‐3922605;2. fax: +49‐6131‐3925396) |
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| Abstract: | Methacrylates (=2‐methylpropenoates) 5 with (E)‐stilbene (=(E)‐1,2‐diphenylethene) building blocks on tethers of variable length were prepared (Scheme 2) and polymerized (i.e., 5 → 6 ; Scheme 3) in the presence of AIBN (=2,2′‐azobis(2‐methylpropanenitrile). 4‐(E)‐2‐Phenylethenyl]phenyl acetate ( 7 ) as model compound established the cyclodimerization as a single irreversible photoreaction. i.e., ( 7 → 8 – 11 ; Scheme 4) in the absence of oxygen. The solution photolysis of the polymers 6 provided a similar result, whereby 2π+2π] cycloadditions of stilbene units of neighboring tethers predominated. On the contrary, the desired photo‐cross‐linking of chaines occurred in the irradiation of polymer films. |
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| Keywords: | Cross‐linking Cycloadditions Photochemistry Polymethacrylates Stilbene |
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