Thiazolopyrimidnes are considered one of the most interesting classes in heterocyclic chemistry due to their pharmaceutical importance. Herein, we report the synthesis of some new heterocyclic compounds containing thiazolopyrimidine starting from compound (1) which was previously prepared in literature. The starting compound was allowed to react with different alkylating agents such as chloroacetone, chloroacetyl chloride, and phenacyl bromide to afford derivatives (2-4). Compound (5), benzylidene derivative, was obtained by the reaction of compound (2) with benzaldehyde while amino-dicarbonitrile compound (6) can be obtained by the reaction of compound (5) and malononitrile. Acetylation of amino group in compound (6) with chloroacetyl chloride led to formation of compound (7). Nucleophilic substitution of chlorine in compound (7) by aniline gave compound (8) which further subjected the Munich reaction to form compound (9). All new synthesized compounds were characterized using different elemental and spectral analysis.

Herein, we report the efficient preparation of π-electron-extended triazine-based covalent organic framework (TFP-TPTPh COF) for photocatalysis and adsorption of the rhodamine B (RhB) dye molecule, as well as for photocatalytic hydrogen generation from water. The resultant TFP-TPTPh COF exhibited remarkable porosity, excellent crystallinity, high surface area of 724 m2 g−1, and massive thermal stability with a char yield of 63.41%. The TFP-TPTPh COF demonstrated an excellent removal efficiency of RhB from water in 60 min when used as an adsorbent, and its maximum adsorption capacity (Qm) of 480 mg g−1 is among the highest Qm values for porous polymers ever to be recorded. In addition, the TFP-TPTPh COF showed a remarkable photocatalytic degradation of RhB dye molecules with a reaction rate constant of 4.1 × 10−2 min−1 and an efficiency of 97.02% under ultraviolet–visible light irradiation. Furthermore, without additional co-catalysts, the TFP-TPTPh COF displayed an excellent photocatalytic capacity for reducing water to generate H2 with a hydrogen evolution rate (HER) of 2712 μmol g−1 h−1. This highly active COF-based photocatalyst appears to be a useful material for dye removal from water, as well as solar energy processing and conversion.

Here, we describe a simple method to synthesize the starting intermediate 2‐amino‐8‐benzylidene‐4‐phenyl‐5,6,7,8‐tetrahydro‐4H‐chromene‐3‐carbonitrile (6) by the reaction of 2,6‐dibenzylidene cyclohexanone with malononitrile in the presence of triethyl amine under solvent‐free conditions. The o‐amino carbonitrile compound 6 was used as a versatile precursor for synthesis of novel heterocyclic compounds fused to the 4H‐chromene ring system heterocycles 7–17 such as chromenopyrimidines, chromenoimidazopyrimidine, chromenopyrimidotriazepinone, and chromenotriazolopyrimidine. The chemical structures of the newly synthesized compounds were established on the basis of elemental and spectral analyses including melting point, thin‐layer chromatography, Fourier transform infrared spectroscopy, 1H‐NMR, and mass spectroscopy, hoping these molecules would allow us to investigate their pharmacological activities in future studies.