Photophysical Properties and pH Sensing Applications of Luminescent Salicylaldehyde Derivatives

J. Y. Liu, J. H. Cheng, X. F. Ma, X. G. Zhou, and H.F. Xiang,* Research on Chemical Intermediates, 2016, 42, 5027-5048.

众所周知，水扬醛及其简单的衍生物只拥有一个苯环，其共轭体系很小，所以其在室温下基本上没有荧光。学生在实验中偶然发现在碱性条件下，其荧光大大增强，荧光量子产率可高达0.35。。。这篇文章首先投到ACS Appl. Mater. Interfaces，审稿意见回来两个小修、一个拒搞，主编直接拒搞。我们没有申诉，按照审稿人的意见，仔细修稿后，直接再投ACS Appl. Mater. Interfaces，结果还是一样，两个修改、一个拒搞，主编再次直接拒搞。然后没办法再投ACS Appl. Mater. Interfaces，只好投其它杂志。。。可是越往下投，回来的审稿意见越差，差点都放弃了。。。但是，最后还是给它找了一个家！

前后折腾两年多，结果不是很理想，综合审稿意见，总结了一下原因。还是做得太简单，多数水扬醛都是买来的，太简单的体系，虽然发现的结果我自认为很有趣和很有用。

做研究不是越简单越好！！！投文章就像娱乐明星要有花边新闻一样，文章要越复杂越好，越炫越好！！！仿佛大家包括我自己都迷失研究的目的。。。

The photophysical properties, density functional theory calculations, and pHsensing applications of a series of salicylaldehyde derivatives that contain only one small p-conjugated benzene ring system are reported. The steric, electronic and p-extended effects on their photophysical properties arefully investigated. The presence of donor-acceptor (DA) system ensures not only blue, green, and yellow emission, but also high fluorescence quantum yields up to 0.35 in DMF at room temperature. The absorption and fluorescence properties of the salicylaldehyde derivatives arehighly dependent on the pH value of the solution, which realize their applications in pH sensing and living cell imaging. The pK_a values of these compounds ranging from 4.6 to 9.6 can be well tuned by their structures. Moreover, in order to achieve good solubility in water, sodium sulfonato groupwas introduced into the salicylaldehyde derivatives, which are very useful for tuning pK_a values and detecting pH values in water.