Heterogeneous catalysts based on materials with permanent porosity are of great interest owing to their high specific surface area, easy separation, recovery, and recycling ability. Additionally, porous polymer catalysts (PPCs) allow us to tune catalytic activity by introducing various functional centres. This study reports the preparation of PPCs with a permanent micro/mesoporous texture and a specific surface area S of up to 1000 m g active in acid-catalyzed reactions, namely aldehyde and ketone acetalization and carboxylic acid esterification. These PPC-type conjugated hyper-cross-linked polyarylacetylene networks were prepared by chain-growth homopolymerization of 1,4-diethynylbenzene, 1,3,5-triethynylbenzene and tetrakis(4-ethynylphenyl)methane. However, only some ethynyl groups of the monomers (from 58 to 80 %) were polymerized into the polyacetylene network segments while the other ethynyl groups remained unreacted. Depending on the number of ethynyl groups per monomer molecule and the covalent structure of the monomer, PPCs were decorated with unreacted ethynyl groups from 3.2 to 6.7 mmol g . The hydrogen atoms of the unreacted ethynyl groups served as acid catalytic centres of the aforementioned organic reactions. To the best of our knowledge, this is first study describing the high activity of hydrogen atoms of ethynyl groups in acid-catalyzed reactions.

The spontaneous, catalyst free polymerization of four monomers of the bis(pyridyl)acetylene and bis[(pyridyl)ethynyl]benzene types containing either 2-pyridyl or 4-pyridyl groups via activation with benzyl bromide leads to ionic π-conjugated polyacetylene-type polyelectrolytes (CPEs). All polymers are characterized by means of NMR, IR, UV/vis and photoluminescence spectroscopies, thermogravimetric analysis (TGA) and matrix assisted laser desorption/ ionization time of fl ight mass spectrometry (MALDI-TOF MS). The position of the pyridyl groups in the monomer infl uences the degree of quaternization and the extent of conjugation of CPEs. Monomers with 4-pyridyl groups provide CPEs with a low extent of quaternization [N + /(N + + N) = 0.27-0.34] and high extent of conjugation. On the other hand, the CPEs derived from 2-pyridyl-containing monomers are highly quaternized [N + /(N + + N) = 0.77-1.00], however, possess lower conjugation of the main chains. The mechanism assuming quaternization and polymerization as competitive reactions is proposed to explain the difference in the extent of quaternization of CPEs. Prepared CPEs i) are well soluble in polar solvents, e.g., water, methanol, dimethyl sulfoxide, and dimethylformamide, ii) exhibit photoluminescence (emission in the violet to yellow region), and iii) possess high thermal stability. materials with a wide variety of applications, [1][2][3][4][5][6][7][8] including light-emitting diodes (LEDs), [ 9 ] light-emitting electrochemical cells (LECs), [ 10 ] plastic lasers, [ 11 ] solar cells, [ 12 ] fi eld-effect transistors (FETs) [ 13 ] and porous materials. [ 14,15 ] The π-conjugated polyelectrolytes (CPEs) represent a special subclass of CPs. [ 16 ] The CPE polymers comprise π-conjugated main chains and ionic and/or ionizable groups. Unlike the majority of neutral CPs, CPEs additionally exhibit i) solubility in polar solvents as water, aqueous solutions, alcohols, and others environmentally friendly solvents, [17][18][19] ii) amphiphilic nature, which gives CPE macromolecules capability of self-assembling in solutions and ability to interact specifi cally with particular species under measurable optical and/or electrical responses, and iii) simultaneous electronic and ionic conductivity [ 20 ] reducing the electron-injection barrier Emission spectra 400 450 500 550 600 650 Wavelength (nm) Br N N N N N N N N N N Br Br Br Br Br NO CATALYST poly(4PD)

This study reports the first Co (CO) -catalyzed [2+2+2] polycyclotrimerization by the transformation of internal ethynyl groups of aromatic diyne monomers. The reaction yields polycyclotrimers of polyphenylene-type with either hyperbranched or partly crosslinked architecture. The homopolycyclotrimerization of the monomers with two ethynyl groups per one molecule, namely 1,4-bis(phenylethynyl)benzene, 4,4'-bis(phenylethynyl)biphenyl, and 4-(phenylethynyl)phenylacetylene, gives partly crosslinked, insoluble polyphenylenes. The soluble, hyperbranched polyphenylenes are generated via copolycyclotrimerization of 1,4-bis(phenylethynyl)benzene with 1,2-diphenylacetylene (average number of ethynyl groups per monomer molecule < 2). This one-step polycyclotrimerization path to hyperbranched or partly crosslinked polyphenylenes is an alternative to the synthesis of these polymers by Diels-Alder transformation of substituted cyclopentadienones. All polyphenylenes prepared exhibit photoluminescence with emission maxima ranging from 381 to 495 nm. Polyphenylenes with a less compact packing of segments are microporous (specific surface area up to 159 m g ), which is particularly important in the case of soluble polyphenylenes because they can be potentially used to prepare microporous layers.

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Four monomers of the bis(pyridyl)acetylene and bis[(pyridyl)ethynyl]benzene types containing either 2‐pyridyl or 4‐pyridyl groups are polymerized into respective networks of the conjugated polyelectrolyte (CPE) type by catalyst‐free polymerization via activation with 1,4‐bis(bromomethyl)benzene as quaternization agent (QA). Prepared CPE networks are characterized by elemental analysis (EA), TGA analysis, 13C cross‐polarization magic‐angle spinning NMR, IR, UV/vis, and photoluminescence spectroscopies. Highly cross‐linked network structure containing both π‐conjugated polyacetylene type chains and ionic alternating type chains is proposed. According to EA analysis, the mole ratio of units derived from monomer molecules and QA molecules is close to unity in all prepared networks. The CPE networks based on 4‐pyridyl monomers exhibit strong photoluminescence in the visible region after irradiation with light of wavelength of 378 nm. Prepared CPE networks also show moderate efficiency in CO2 sorption up to 13.6 cm3 g−1 (STP) and exceptionally high ethanol vapor capture efficiency up to 24.5 wt% (293 K). The specific interactions of ionic network and adsorbed molecules and also temporary pores formation are assumed to play important role in sorption processes.

The chain coordination polymerization of (ethynylarene)carbaldehydes with unprotected carbaldehyde groups, namely ethynylbenzaldehydes, 1-ethynylbenzene-3,5-dicarboxaldehyde, and 3-[(4-ethynylphenyl)ethynyl]benzaldehyde, is reported for the first time. Polymerization is catalyzed with various Rh(I) catalysts and yields poly(arylacetylene)s with one or two pendant carbaldehyde groups per monomeric unit. Surprisingly, the carbaldehyde groups of the monomers do not inhibit the polymerization unlike the carbaldehyde group of unsubstituted benzaldehyde that acts as a strong inhibitor of Rh(I) catalyzed polymerization of arylacetylenes. The inhibition ability of carbaldehyde groups in (ethynylarene)carbaldehydes seems to be eliminated owing to a simultaneous presence of unsaturated ethynyl groups in (ethynylarene)carbaldehydes. The reactive carbaldehyde groups make poly[(ethynylarene)carbaldehyde]s promising for functional appreciation via various postpolymerization modifications. The introduction of photoluminescence or chirality to poly(ethynylbenzaldehyde)s via quantitative modification of their carbaldehyde groups in reaction with either photoluminescent or chiral primary amines under formation of the polymers with Schiff-base-type pendant groups is given as an example.