†Graduate School of Materials Science, Nara Institute of Science and Technology, NAIST, Ikoma, Nara 630-0192, Japan.
‡NAIST-CEMES International Collaborative Laboratory for Supraphotoactive Systems, NAIST, CEMES-UPR 8011 CNRS, 29, rue Jeanne Marvig, BP 94347, 31055 Toulouse Cedex 4, France.
J Am Chem Soc. 2015 Jun 10;137(22):7023-6. doi: 10.1021/jacs.5b02826. Epub 2015 Jun 1.
We herein propose a new type of efficient neutral photoacid generator. A photoinduced 6π-electrocyclization reaction of photochromic triangle terarylenes triggers subsequent release of a Brønsted acid, which took place from the photocyclized form. A H-atom and its conjugate base were introduced at both sides of a 6π-system to form the self-contained photoacid generator. UV irradiation to the 6π-system produces a cyclohexa-1,3-diene part with a H-atom and a conjugate base on the sp(3) C-atoms at 5- and 6-positions, respectively, which spontaneously release an acid molecule quantitatively forming a polyaromatic compound. A net quantum yield of photoacid generation as high as 0.52 under ambient conditions and a photoinitiated cationic polymerization of an epoxy monomer are demonstrated.
我们在此提出了一种新型高效的中性光酸产生剂。光致变色三角三苯并烯的光诱导 6π-电环化反应引发随后释放出布朗斯台德酸，该反应从光环化形式发生。在 6π-体系的两侧引入 H-原子及其共轭碱，形成自包含的光酸产生剂。UV 辐照到 6π-体系会产生一个环己-1,3-二烯部分，在 5-和 6-位的 sp(3) C 原子上分别带有 H-原子和共轭碱，它们会自发定量释放出一个酸分子，形成一个多环芳烃化合物。在环境条件下，光酸生成的量子产率高达 0.52，并且可以引发环氧单体的光引发阳离子聚合。
