Synthesis and characterisation of polymerisable photochromic spiropyrans: towards photomechanical biomaterials
- 作者：Colin P. McCoy ; Louise Donnelly ; David S. Jones ; Sean P. Gorman
- 关键词：Spiropyran ; Merocyanine ; Polymerisable ; Photochromism
- 刊名：Tetrahedron Letters
- 出版年：2007
- 期刊代码：109_00404039
- 类别：ch
- 出版时间：22 January 2007
- 卷：48
- 期：4
- 页码：657-661
- 文件大小：185 K
摘要
A methodology for the synthesis of novel polymerisable spiropyrans with photomechanical properties suitable for subsequent copolymerisation with either vinyl or acrylate-based biomaterials is described. UV–vis spectroscopic characterisation of photoisomerism shows that photochromic behaviour with respect to related non-polymerisable compounds is retained and is solvent dependent. In acetone, conventional spiropyran–merocyanine photochromism is observed for nitro-spiropyran derivatives, whereas in dichloromethane both nitro-spiropyrans and spiropyrans isomerise to merocyanines which rapidly form H-aggregates. The monomers were designed such that an alkyl spacer of variable length, both electronically and sterically, separates the polymerisable moiety from the photochromic core and allows steric aspects of the resulting photomechanical behaviour to be explored.