Precise 2D‐Patterned Incompatible Catalysts for Reactions in One‐Pot. Issue 59 (19th September 2019)

• Record Type: Journal Article
• Authors: Pretscher, Martin O.; Chen, Tingting; Sitaru, Gabriel; Gekle, Stephan; Ji, Jian; Agarwal, Seema
• Is Part Of: Chemistry. Volume 25:Issue 59(2019)
• Page Start: 13640
• Page End: 13646
• Publication Date: 2019-09-19
• Subjects: heterogeneous catalysis -- immobilization -- multicomponent reactions -- nanostructures -- polymers -- solid-state structures; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201903486
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Precise and direct two‐dimensional (2D) printing of the incompatible polymer acid–base catalysts and their utility in one‐pot two‐step reactions were shown. Multistep catalytic reactions using incompatible catalysts in a one‐pot reaction cascade requires special methods and materials to isolate the catalysts from each other. In general, this is a tedious process requiring special polymer architectures as the carrier for the catalysts to preserve the activity of otherwise incompatible catalysts. We propose the immobilization of incompatible polymer catalysts, such as polymer acid and base catalysts, on a substrate in variable sizes and amounts by precise 2D printing. The terpolymers with basic (4‐vinylpyridine) and acidic (styrene sulfonic acid) functionalities and methacryloyl benzophenone as a UV cross‐linking unit were used for 2D printing on poly(ethylene terephthalate) (PET). The printed meshes were immersed together in a reaction solution containing (dimethoxymethyl)benzene and ethyl cyanoformate, resulting in a two‐step acid–base catalyzed cascade reaction; that is, deacetalization followed by carbon‐building reaction. The time‐dependent consumption of (dimethoxymethyl)benzene to the intermediate benzaldehyde and the product was monitored, and a kinetic model was developed to investigate the underlying reaction dynamics. The complexity of multistep Wolf–Lamb‐type reactions was generally significantly decreased by using our approach because of the easy polymerization and immobilization procedure. Abstract : Printed catalysts : 2D patterned structures were used as Wolf–Lamb‐type catalysts (see figure). Thus, acid and base polymers were synthesized, printed on separate PET, cross‐linked by UV light and then immersed in solution to monitor the kinetics of the multistep, one‐pot catalysis. The kinetic constants were calculated using differential equations.