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All the reagents employed were available from commercial sources and were used without further purification. Freshly distilled solvents were used for the synthesis. Column chromatography was performed using silica gel of 100-200μ mesh. 1 H and 13 C NMR spectra were recorded on JEOL-Lambda spectrometers. IR spectra were recorded on a Bruker Vector 22 FT-IR spectrometer. Melting points were measured using a JSGW melting point apparatus. High-resolution mass spectra (HRMS) were recorded on a Waters ESI-QTOF machine. Thermogravimetric analyses were carried out with a SDT-Q600TGA apparatus under N2 atmosphere with a heating rate of 10 °C/min. SEM images were recorded on a Nova Nano SEM 450 FE-SEM scanning electron microscope. TEM images were recorded on a carbon-coated Cu grid on a Bruker Nano GmbH HRTEM. XPS analyses were carried out on an X-ray photoelectron spectroscopy module (PHI 5000 Versa Prob II, FEI Inc.). Elemental analyses were performed with vario MICRO Element Analyzer. The gas adsorption and desorption studies were performed using a Quantachrome AutosorbiQ automated gas sorption analyzer. The average pore size and average pore distributions were calculated NLDFT methods using the N2 sorption isotherms. The substituted propargyl alcohols, i.e., 1-(4-(tert-butyldimethylsilyloxy)phenyl)-1-phenylprop-2-yn-1-ol, 1 3-(tert-butyldimethylsilyloxy)-9-ethynyl-9H-fluoren-9-ol, 1 1,1-bis(4-(tertbutyldimethylsilyloxy)phenyl)prop-2-yn-1-ol, 1 1,1-bis(4-methoxyphenyl)prop-2-yn-1-ol 2 and 9ethynyl-9H-fluoren-9-ol, 2 were synthesized according to reported procedures. S3 Scheme S1. Synthesis of 2,2',6,6'-Tetramethylbiphenyl (MeM) 3 A two-necked round-bottomed flask was charged with magnesium turnings (0.2 g, 8.1 mmol), 30 mL of dry THF and 0.1 mL of 1,2-dibromoethane under N2 atmosphere and stirred at rt for 15 min. Subsequently, 2-bromo-m-xylene (1.0 g, 5.4 mmol) was added over a period of 15 min and the reaction mixture was stirred at rt for further 1.5 h. At the end of this period, the resultant Grignard reagent was added slowly to a suspension of FeCl3 (1.31 g, 8.1 mmol) in dry THF (20 mL) taken in another round-bottom flask under N2 atmosphere at ice-cold conditions. After completion of the addition, the reaction mixture was allowed to attain rt and subsequently heated to reflux for 4 h. At the end of this period, the reaction mixture was carefully quenched with icecold water and the organic matter was extracted with CHCl3 (3 × 30 mL). The combined organic extract was dried over Na2SO4 and concentrated under reduced pressure. The pure product was obtained by silica gel column chromatography, yield 0.88 g (78%), 1 H NMR (CDCl3, 400 MHz) δ 1.94 (s, 12H), 7.14−7.19 (m, 6H). Scheme S2. Synthesis of 2,2',6,6'-Tetramethoxybiphenyl (OMeM) 4 To the mixture of 1,3-dimethoxybenzene (1.0 g, 7.24 mmol) and TMEDA (1.2 mL, 7.96 mmol) in dry THF (40 mL) at-78 °C was slowly added a solution of n-BuLi (1.6 M in hexane, 6.25 mL, 8.7 mmol) under N2 atmosphere. Subsequently, the reaction mixture was allowed to attain 0 °C and stirred at...

Two porous organic polymers (POPs), namely, ANT and NAP based on N,N,N′,N′-tetrakis(4-acetylphenyl)anthracene-9,10-diamine and N,N,N′,N′-tetrakis(4acetylphenyl)naphthalene-1,4-diamine, respectively, as core scaffolds and enone functionalities as the connecting backbones, were synthesized using an aldol condensation reaction. The enone backbones of the POPs mimic α,β-unsaturated ketone functionalities of dibenzylideneacetone (dba), which is frequently employed to stabilize Pd(0), e.g., Pd 2 (dba) 3 , for effective utilization in the catalysis of a myriad of organic transformations. We have thus leveraged the chalcone motifs inherent to ANT and NAP for stabilization of Pd(0) or Cu(0) nanoparticles (NPs) to provide access to POPs embedded with Pd(0) and Cu(0) nanoparticles, i.e., Pd@ANT, Pd@NAP, Cu@ANT, and Cu@NAP. Pd@POPs are shown to be applicable to facile synthesis of therapeutically useful N-arenesulfonylindoles and 2-arylbenzofurans by tandem Songashira coupling−cyclization reactions in a recyclable manner without any perceptible loss of their catalytic efficiency for up to 15 catalytic cycles. In a similar manner, Cu@POPs are shown to serve for expedient synthesis of (i) 1-aryl-1H-indazoles by tandem imine formation− Ullmann coupling, and (ii) unsymmetrical diaryl selenides by tandem activation of diphenyl diselenide−coupling with arylboronic acids in a recyclable fashion for up to eight catalytic cycles. The results thus attest to the fact that mechanisms that allow stabilization of nanoparticles can be built into the design of building blocks to develop, in a bottom-up fashion, robust POPs as supports, which obviate leaching issues and permit recyclability by precluding any loss in the catalytic efficacy of the catalysts. Furthermore, it is shown that POPs exhibit selective adsorption of clean and green fuel, namely, hydrogen gas over nitrogen, with a very high selectivity factor.