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Waste date palm fiber (DPF) has recently emerged as a promising natural fiber due to its abundance, renewability, and low cost. The study discussed the use of DPF as reinforcement in composites, particularly in polybenzoxazine (PBz), epoxy resin (EP), and their copolymer (EP‐co‐PBz) composites. The waste DPF underwent an alkaline treatment process, resulting in a high‐performance material that exhibits exceptional interaction with the matrix. The composite samples were fabricated using 5–20 wt% of alkali treated DPFs with polybenzoxazines and epoxy resins. The study examined the thermal and morphological properties of the resulting composites and found that they exhibited remarkable enhancements in various properties. For instance, the PNaphz‐COOH reinforced 5 wt% DPFs composite showed a significant increase in Td5% and Td10%, while the EP‐co‐PBz reinforced DPFs composites exhibited a remarkable increase in char yield (Yc). The SEM analysis of the composite surface further validated these findings, highlighting the remarkable interfacial bonding between the DPFs and the matrix. The remarkable enhancements in thermal properties demonstrated in this study open up new possibilities for utilizing waste DPF in various applications. Highlights: Waste date palm fiber enhances thermosetting polymer reinforcement for high‐performance composites.Alkaline treatment improves interfacial bonding between waste DPF and matrix.Composites reinforced with waste DPF exhibit outstanding thermal and morphological properties. [ABSTRACT FROM AUTHOR]

Repetitive Mizoroki‐Heck (MH) coupling polymerization was used to create novel chiral polyureas with cinchona alkaloids in the main chain. Apart from two‐component polycondensation of cinchona urea dimers with diiodobenzene via MH reaction conditions, some chiral polyureas were easily polymerized under self polycondensation to yield the chiral polymers. The asymmetric Michael addition reaction was successfully carried out using chiral polymers derived cinchona urea. Interestingly, phenolic‐based chiral polymers served as heterogeneous catalysts for the enantioselective Michael reaction, with high catalytic activity and excellent enantioselectivities (up to 99 % ee). These polymeric catalysts were also stable, and they could be recycled and reused. [ABSTRACT FROM AUTHOR]

Chiral polyureas of cinchona alkaloids were synthesized via repetitive Mizoroki‐Heck (MH) coupling reaction. The Pd‐catalyzed polycondensation of cinchona urea dimers 6 and aromatic diiodide 7 afforded the chiral polyureas (P1−P4). The catalytic activity of the chiral polymers was subsequently investigated. The asymmetric Michael addition of ketoesters to nitroolefins was successfully catalyzed by the polymeric organocatalysts (P1−P4) to give the corresponding Michael adducts with high catalytic activities and excellent enantionselectivities (up to >99% ee). The polymeric catalysts were insoluble in commonly used organic solvents. They were easily recovered and reused several times without any loss of the catalytic activity. [ABSTRACT FROM AUTHOR]

1,3-Dihydroimidazole-2-thiones 1a-d were desulfurized by hydrogen peroxide in either acid or neutral medium to afford 1Himidazoles 3a-d. Reaction of 3b,d with dimethylsulfamoyl chloride furnished N,N-dimethylsulfamoylimidazoles 5 and 6a,b. Lithiation of 5 and 6a,b followed by formylation and reduction yielded the 2-hydroxymethyl derivatives 7 and 8a,b. 4-Alkyl-5-cyclohexylmethyl-1H-imidazol-2-yl)methanols 9a,b were obtained by hydrolysis of 7 and 8a,b. [ABSTRACT FROM AUTHOR]

alpha-Aminoketone hydrochlorides 2a-d were synthesized by Dakin-West reaction from L-phenylalanine and L-cyclohexylalanine followed by hydrolysis in acidic medium. Treatment of 2a-d with aqueous potassium thiocyanate afforded 1, 3-imidazole-2-thiones 3a-d which were alkylated with methyl iodide to give 2-methylsulfanyl-1H-imidazoles 4a-d with 4-benzyl/4-cyclohexylmethyl and 5-ethyl/5-isopropyl substituents. Coupling of 4a-d with ethoxymethyl chloride or benzyloxymethyl chloride furnished N-1 5a-d and N-3 6a-h alkylated products. The synthesised compounds were tested for their activity against HIV-1. The most active compounds have a cyclohexylmethyl group in the 5-position of 6 and showed an activity against HIV-1 comparable to the activity of Nevirapine.