Sulfonated Hyper‐cross‐linked Porous Polyacetylene Networks as Versatile Heterogeneous Acid Catalysts

Abstract

Two highly sulfonated micro/mesoporous polymers, P(1,3‐DEB)‐SO3H and P(1,4‐DEB)‐SO3H, with permanent porosity, the specific surface area about 550 m2 ⋅ g−1 and the content of SO3H groups of 2.7 mmol ⋅ g−1 were prepared as new acid Porous Polymer Catalysts, PPCs. The PPCs were achieved by easy sulfonation of parent hyper‐cross‐linked micro/mesoporous polyacetylene‐type networks resulting from a chain‐growth homopolymerization of 1,3‐ and 1,4‐diethynylbenzenes. New PPCs are reported as highly active and reusable heterogeneous catalysts of esterification of fatty acids with methanol and ethanol, Prins cyclization of aldehydes with isoprenol and intramolecular Prins cyclization of citronellal to isopulegol. The catalytic activity of the micro/mesoporous PPCs (TON values up to 522 mol ⋅ mol−1) was higher than that of commercial polymer‐based heterogeneous catalyst Amberlyst 15 possessing gel texture without permanent pores and that of p‐toluenesulfonic acid applied as a homogeneous catalyst.

Microporous Hyper‐Cross‐Linked Polymers with High and Tuneable Content of Pyridine Units: Synthesis and Application for Reversible Sorption of Water and Carbon Dioxide

“…The fact that the values of the textural parameters of pyridine‐containing networks were somewhat lower than those found for the purely hydrocarbon network P(DEB) (Table 1) corresponds to the literature describing the decrease in textural parameters of microporous polymers due to the introduction of heteroatoms into their covalent structure. [ 32,47,51 ] In summary, the one‐step polymer synthesis consisting of the chain‐growth polymerization of diethynylpyridines provided POPs of hyper‐cross‐linked‐type with moderate values of textural parameters and a high (and tuneable) content of pyridine units (up to 7.86 mmol g −1 ), which were potentially suitable for adsorption applications.…”

“…[ 46 ] The resulting POPs consisted of polyacetylene (polyene) main chains that were hyper‐cross‐linked by arene‐type cross‐links. [ 22 ] Polyacetylene POPs were active as heterogeneous catalysts, [ 47 ] sorbents, [ 10 ] and porous fluorescent materials. [ 48 ]…”

Synthesis of Sulfonated Porous Organic Polymers with a Hydrophobic Core for Efficient Acidic Catalysis in Organic Transformations

“…Compared with inorganic and carbonaceous materials, porous organic polymers (POPs) constitute a more suitable and versatile platform for the development of solid acid catalysts due to some potential advantages, such as high surface area, excellent structural stability, enhanced hydrophobicity, and tailorable chemical functionality [12–18] . For this reason, sulfonated porous organic polymers have been widely used as efficient solid acid catalysts in various organic reactions including, hydration, dehydration and particularly in biodiesel production through the esterification of free fatty acids and transesterification of triglycerides [19–28] . Considerable progress has been made in developing methods for the synthesis of sulfonated porous organic polymers.…”

Acid Functionalized Conjugated Microporous Polymers as a Reusable Catalyst for Biodiesel Production

“…19 Natural oils and fats generally consist of triglycerides and free fatty acids (FFAs) that can be converted to biodiesel such as fatty acid methyl ester (FAME) via transesterification and esterification with methanol, respectively. 18 Porous polymers derived from both natural and synthetic materials have been widely applied as catalysts for various organic reactions such as selective oxidation [21][22][23][24] , Sonogashira-Hagihara cross coupling 25 , dehydration of fructose to 5-hydroxymethylfurfural (HMF) 26 and biodiesel production [27][28][29][30][31][32][33][34][35][36] . Recently, different acid functionalized porous polymers have been synthesized and utilized as catalysts for biodiesel production due to their large surface area, high acidity and excellent thermal and chemical stability.…”

“…Recently, different acid functionalized porous polymers have been synthesized and utilized as catalysts for biodiesel production due to their large surface area, high acidity and excellent thermal and chemical stability. [29][30][31][32][33][34][35][36] For instance, a sulfonated HCP derived from carbazole has previously been prepared by Bhunja et al and was applied as an acid catalyst for biodiesel production from FFAs at room temperature. The synthesized catalyst exhibited high yield of FAME products and excellent recyclability.…”