Wavelength-Selective Caged Surfaces: How Many Functional Levels Are Possible?
作者:Verónica San Miguel、Christian G. Bochet、Aránzazu del Campo
DOI:10.1021/ja110572j
日期:2011.4.13
The possibility of wavelength-selective cleavage of seven photolabile caging groups from different families has been studied. Amine-, thiol-, and carboxylic-terminated organosilanes were caged with o-nitrobenzyl (NVOC, NPPOC), benzoin (BNZ), (coumarin-4-yl)methyl (DEACM), 7-nitroindoline (DNI, BNI), and p-hydroxyphenacyl (pHP) derivatives. Caged surfaces modified with the different chromophores were prepared, and their photosensitivity at selected wavelengths was quantified. Different pairs, trios, and quartets of chromophore combinations with wavelength-selective photoresponse were identified. Our results show, for the first time, the possibility of generating surfaces with up to four different and independently addressable functional levels. In addition, this manuscript presents the first systematic comparison of the photolytic properties of different photolabile groups under different irradiation conditions.
Light-Sensitive Protecting Groups for Amines and Alcohols: The Photosolvolysis of N-Substituted 7-Nitroindolines
作者:Alfred Hassner、Diana Yagudayev、Tarun Pradhan、Abraham Nudelman、Boaz Amit
DOI:10.1055/s-2007-985580
日期:2007.9
Representative examples of primary and secondary amines were protected as urea derivatives 4 of 5-bromo-7-nitro-indoline and even more efficiently as ureas 8 derived from 5,7-di-nitroindoline, via high-yield reactions with carbamoyl chlorides 3 and 7, respectively. Deprotection of 4 or 8 was achieved in high yields by UV irradiation at room temperature in Pyrex vessels under neutral conditions and