Tricyclohexylphosphine-Catalyzed Cycloaddition of Enynoates with [60]Fullerene and the Application of Cyclopentenofullerenes as n‑Type Materials in Organic Photovoltaics

The tricyclohexylphosphine-catalyzed [3 + 2] cycloaddition of (<i>E</i>)-alkyl 5-substituted phenylpent-4-en-2-ynoates with [60]­fullerene was studied. This reaction undergoes an initial 1,3-addition of phosphines toward the α-carbons of enynoates. Subsequent cycloaddition of the generated 1,3-dipoles with [60]­fullerene and elimination of tricyclohexyl­phosphines resulted in cyclo­penteno­fullerenes in 20–43% yields. The isolated cyclo­penteno­fullerenes were observed to serve as n-type materials in organic photovoltaics, providing a maximum average power conversion efficiency of 3.79 ± 0.29% upon embedding with P3HT in the active layer

Sterically Polymer-Based Liposomal Complexes with Dual-Shell Structure for Enhancing the siRNA Delivery

The sterically polymer-based liposomal complexes (SPLexes) were formed by cationic polymeric liposomes and pH-sensitive diblock copolymer were studied for their capabilities in improving the stability with high efficiency of siRNA delivery. The SPLexes were formed a dual-shelled structure and uniform size distribution. The PEGylated outer shell could mitigate the phagocytosis and reduce the cytotoxicity. Moreover, the folated SPLexes improved 42.9× accumulation in vitro and 1.7× tumor uptake in vivo in contrast with nonfolated SPLexes. The protonated copolymer at low pH would improve the siRNA released into cytoplasm following SPLexes fusion with the endo/lysosome membrane and inhibited the protein expression to 75.6 ± 4.5% efficiently. Results of this study significantly contribute to efforts to develop lipoplexes based siRNA delivery systems