The Synthesis of Chiral Periodic Organosilica Materials with Ultrasmall Mesopores

Decarboxylative Iodination and Suzuki-Miyaura Coupling Reactions to Access Chiral 3,3'-Diaryl-1,1'-bi-2-naphthols

An efficient synthesis of the enantiomerically pure 3,3'-bis-arylated BINOLs is accomplished through decarboxylative iodination of the dimethyl ether derivative of BINOL-3,3'-dicarboxylic acid followed by Suzuki-Miyaura coupling using a one-pot protocol. The decarboxylative iodination is effected with the dimethyl ether derivative of BINOL-3,3'-dicarboxylic acid using iodine as a terminal oxidant and the cheaply available K3PO4 as a base under neat conditions. This protocol facilitated the introduction of the aryl group at the 3,3'-position on the binaphthyl system using aryl boronic acid through a palladium-catalyzed Suzuki-Miyaura coupling reaction.

Tunable mesoporous bilayer photonic resins with chiral nematic structures and actuator properties

Chiral nematic structures with different helical pitch from layer to layer are embedded into phenol-formaldehyde bilayer resin composite films using cellulose nanocrystals (CNCs) as templates. Selective removal of CNCs results in mesoporous resins with different pore size and helical pitch between the layers. Consequently, these materials exhibit photonic properties by selectively reflecting lights of two different wavelengths and concomitant actuation properties.

Facile construction of functionalized periodic mesoporous organosilica for Ir-catalyzed enantioselective reduction of α-cyanoacetophenones and α-nitroacetophenones

A facile construction of organoiridium-functionalized periodic mesoporous organosilica and its application in the enantioselective reduction of α-cyano and α-nitroacetophenones are studied.

Helium ion microscopy: a new tool for imaging novel mesoporous silica and organosilica materials

Helium ion microscopy (HIM) has been used to image mesoporous silica and organosilica for the first time. Images of chiral nematic silica, ethylenesilica, and new benzenesilica reveal the structural organization, pore dimensions and connectivity of these materials on the nanometer length scale.

Flexible and iridescent chiral nematic mesoporous organosilica films

Nanocrystalline cellulose (NCC) has been used to template ethylene-bridged mesoporous organosilica films with long-range chirality and photonic properties. The structural color of the organosilica films results from their chiral nematic ordering, can be varied across the entire visible spectrum, and responds to the presence of chemicals within the mesopores. To synthesize these materials, acid hydrolysis was used to remove the NCC template without disrupting the organosilica framework. The resulting mesoporous organosilica films are much more flexible than brittle mesoporous silica films templated by NCC. These materials are the first of a novel family of chiral mesoporous organosilicas with photonic properties.