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The domestic and industrial utilization of cotton fiber is largely restricted primarily due to its highly flammable nature. Although halogen-based molecules impart appreciable flame retardancy to cotton, they have notable disadvantages. This review offers comprehensive coverage of naturally derived flame-retardant molecules as an effective alternative to halogen-based flame-retardants. The source of each type of naturally derived flame-retardants, their structural significance, advantages, and role of additives in enhancing the flame-retardant properties were discussed in detail. Apart from highlighting the significance of lignin, deoxyribonucleic acid (DNA), phytic acid, casein, etc., this review article also discusses flame-retardants derived from chicken feathers, egg shells, and hydrophobins. In addition, this review highlights the limitations associated with the naturally derived flame-retardants and provides future perspectives. [ABSTRACT FROM AUTHOR]

One-pot transformation of N,N-dimethylaniline to fused quinoline derivatives was achieved through sequential oxidative cyclization followed by a concomitant C(sp3)–N cleavage/aromatization reaction. The transformation was successfully carried out under an air atmosphere at room temperature itself. Mechanistic investigations revealed that the reaction follows the radical pathway. In silico studies showed that the synthesized molecules exhibit good caspase-3 inhibitory activity. [ABSTRACT FROM AUTHOR]

Regioselective vicinal difunctionalization of diverse alkene derivatives was successfully carried out using readily available carboxylic acids. Molecular oxygen in the atmospheric air tethered with the substrate to form the corresponding peroxygenated products in good yields. All the reactions were carried out at room temperature itself. Apart from the synthesis of peroxygenated products, hydroacylated products were obtained by utilizing Csp2 hybridized carbonyl radicals instead of Csp3 hybridized alkyl radicals. [ABSTRACT FROM AUTHOR]

A convenient one-pot, two-step methodology was developed for the transformation of readily available planar naphthoquinone derivatives into structurally complex indole-fused nitrogen heterocycles under aerobic conditions. The appropriate structural design in the synthetic protocols offered an opportunity to obtain deep red emitting solid-state fluorescence materials. Mechanistic studies revealed that atmospheric oxygen plays a crucial role in the aforementioned transformation. [ABSTRACT FROM AUTHOR]

Metal‐free N‐heterocyclic carbene (NHC) organocatalysis in D2O medium was elegantly utilised for the synthesis of highly diastereoselective deuterated spiropyran derivatives. Selective deuteration was exclusively achieved on the C5 carbon atom of the pyran ring. Quantum chemical calculations were performed to prove the preferential formation of a single diastereomer from the possible four diastereomers. The scope of NHC organocatalysis in D2O was also extended for the synthesis of deuterated spirooxindole derivative. [ABSTRACT FROM AUTHOR]

Lipophilic NHC catalysis in aqueous medium was reported for the synthesis of biologically relevant (a)symmetrically substituted and unsymmetrically substituted syncarpamide analogues. All the reported reactions were performed in the absence of any expensive metal salts or additives. A diverse array of syncarpamide analogues was obtained in good yields. Lipophilic NHC catalysis was also extended to chemoselective transesterification reactions. [ABSTRACT FROM AUTHOR]

Abstract: β-Amino esters were obtained in up to 78% yield with 72:28–96:4 diastereomeric ratios by the reaction of the chiral titanium enolate of menthyl esters, prepared using the TiCl4/Et3N reagent system with prochiral imines. A representative syn-β-amino ester derivative has been used for the resolution of racemic mandelic acid to obtain a sample with >99% ee in a single step. A representative syn-β-amino ester was converted to the corresponding N-deprotected amino ester using the Pd–C/HCOOH reagent system, and then to the corresponding β-amino acid using the glacial CH3COOH/HCl reagent system, and to the corresponding β-lactam derivative with partial epimerization by the reaction using C2H5MgBr. [Copyright &y& Elsevier]

Fe 3 O 4 -OSO 3 H was identified as an efficient reusable catalyst for the facile synthesis of diarylmethyl indole derivatives under neat condition by C–C bond forming reaction. Fe 3 O 4 -OSO 3 H catalysis was further extended to C–N bond forming reactions and for the synthesis of spermicidal 3,3′-di(indolyl)oxindole derivative. All the products were obtained in good to excellent yields. [ABSTRACT FROM AUTHOR]

[Display omitted] Palladium catalysed addition of arylboronic acid to the readily available 2-cyano-(N -aryl)-acetamide or ethyl-2-cyanoacetate followed by subsequent reaction transform them into the biologically significant 4-arylquinolin-2-one or pyrazolone derivatives. The reaction conditions are robust enough to prevent the hydrolysis of ester/amide moiety during arylation. In addition, the unactivated nitrile moiety in the acetonitrile also converted to the corresponding acetophenone derivative. [ABSTRACT FROM AUTHOR]

Multicomponent reactions performed on the surface of nanostructured zinc oxide gave 3,3-bis(indolyl)indolin-2-one and xanthene derivatives with excellent yields. Both Lewis acidic (Zn 2+ ) and basic (O 2− ) sites on the surface of zinc oxide were utilized to perform the aforementioned transformations. The significance of surface catalysis was further proved by performing the experiment with surface masked zinc oxide. The developed zinc oxide nanocatalyst was reusable up to five times without significant loss in its activity. [ABSTRACT FROM AUTHOR]

• Peroxide-free, atmospheric oxygen assisted methodology developed. • Synergetic Cu/Ag assisted synthesis employed. • One-pot synthesis of benzoylated naphthol achieved. A peroxide-free methodology was developed for the synthesis of benzoylated naphthol/phenol derivatives through oxidative deamination reaction performed under aerobic reaction conditions. A synergistic combination of Cu(OTf) 2 and Ag 2 O was used to convert the aminonaphthols and aminophenols to the corresponding benzoylated derivatives. The definite role of atmospheric oxygen to assist the reaction was proved by performing the reaction in the argon atmosphere. [ABSTRACT FROM AUTHOR]