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 文獻(xiàn)名：An amphiphilic and photoswitchable organocatalyst for the aldol reaction based on a product-imprinted polymer 

作者：An-xun Zheng^a, Cheng-bin Gong^a, Wei-jing Zhang^a, Qian Tang^a, Hai-rong Huang^a, Cheuk-fai Chow^b, Qian Tang^a 

^a    The Key Laboratory of Applied Chemistry of Chongqing Municipality, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China

^b    Department of Science and Environmental Studies, The Education University of Hong Kong, Hong Kong

 

摘要：A series of amphiphilic molecularly imprinted polymers (MIP1, MIP2, MIP3, MIP4, MIP5, and MIP6) containing hydrophobic photoresponsive sites and hydrophilic catalytically active sites were fabricated using bifunctional monomers. These polymers were characterized by scanning electron microscopy, N2 adsorption–desorption analysis, Fourier Transform infrared spectroscopy, thermal gravimetric analysis, and ultraviolet–visible spectroscopy. The catalytic activity of the amphiphilic molecularly imprinted polymer was investigated towards the aldol reaction between p-nitroaldehyde and acetone (a molecular enlargement reaction) in a mixed solvent of DMSO and water at room temperature. The polymer catalyst MIP3 performs best, and displayed good conversions with low catalyst loading (5 mol% of l-hydroxyproline with respect to the aldehyde) and photoswitching properties (photo-regulated conversion difference of 20%). Compared with the corresponding non-imprinted polymer, a higher binding capacity, higher conversion, and better photoswitching properties were obtained when the molecularly imprinted polymer was used as the catalyst, illustrating the importance of the specific cavities in the molecularly imprinted polymer.