O-Phthalic hemithioacetal

The previous example took inspiration from earlier work of Lin et al.18 In their seminal work, Lin and coworkers functionalized the inner pores of MCM-41 with o-phthalic hemithioacetal moieties that are able to react with amines to produce a highly fluorescent isoindole derivative. In order to enhance selectivity in the sense we have discussed above, the solids were also hydrophobized with different groups such as propyl, phenyl, and pentafluorophenyl in a second step. Interestingly, some of these solids displayed a remarkably selective and differentiable response to dopamine versus the less lipophilic glucosamine. The authors also demonstrated that this selectivity was not observed when amorphous (nonporous) silica functionalized with the same organic groups was used, stressing the importance of the 3D... 

A seminal example of a biomimetic material for discrimination by polarity was described by Lin and coworkers in 2001. The authors functionahzed the inner walls of the pores of an MCM-41 solid with an amine-sensitive o-phthalic hemithioacetal. Subsequently, the pores were cofunctionalized with several groups (propyl, phenyl, and pentafluorophenyl) in order to tune their polarity (Figure 19). The extraction of certain amines into the pores... 

---