Recent progresses in pillar[n]arene-based photocatalysis

By fully considering its hydrophobic/electron-rich cavity, planar chirality, as well as rigid chemical structures, pillar[n]arene has the capacity of contributing its molecular recognition, self-assembly, as well as thus obtained advanced hierarchical materials in photocatalysis. In this review, we discussed and summarized the recent progress in pillar[n]arene-based photocatalysis. Interestingly, it was found that pillar[n]arene played diverse roles in photocatalysis, for example, providing host–guest interactions as phase transfer catalyst in photoreduction/dehalogenation/oxidation for improving the water-solubility of substrates and functional molecules, contributing hydrophobic/electron-rich cavity, inducing planar chirality as homogenous catalyst in photocyclodimerization/redox/dehalogenation for catalyzing selective substrates, and serving as building blocks or reactive sites in the fabrication of hierarchical (hybrid) heterogenous catalyst in selective reactions. The recent progress about pillar[n]arene-based phase transfer catalysts, homogeneous catalysts and heterogeneous catalysts in photocatalysis was summarized in this review.