کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5188385 | 1381154 | 2007 | 10 صفحه PDF | دانلود رایگان |
Pyrene-functionalized chiral methylpropargyl esters, (R)-3-butyn-2-yl-1-pyrenebutyrate [(R)-1], (S)-3-butyn-2-yl-1-pyrenebutyrate [(S)-1], (R)-3-butyn-2-yl-1-pyrenecarboxylate [(R)-2], and 3-butyn-2-yl-1-pyrenecarboxylate [(R,S)-2] were polymerized with (nbd)Rh+[η6-C6H5Bâ(C6H5)3] to obtain the corresponding polymers with moderate molecular weights (Mn: 10â500-66â500) in good yields (82-97%). All the polymers were soluble in CHCl3, CH2Cl2, and THF. The polarimetric and CD spectroscopic data indicated that poly[(R)-1], poly[(S)-1], and poly[(R)-2] existed in a helical structure with predominantly one-handed screw sense in these solvents. The helical structure of poly[(R)-1] and poly[(S)-1] was stable upon heating and addition of MeOH, while that of poly[(R)-2] changed upon MeOH addition. The copolymerization of (R)-1 with (S)-1 was also conducted to obtain the copolymers satisfactorily. Poly[(R)-1], poly[(S)-1], and poly[(R)-2] emitted fluorescence smaller than the corresponding racemic copolymers. The fluorescence intensity was tuned by the addition of MeOH to THF solutions of the polymers.
Journal: Polymer - Volume 48, Issue 22, 19 October 2007, Pages 6491-6500