Sulfur-Promoted Synthesis of Benzoxazoles from 2-Aminophenols and Aldehydes

Advances in the synthetic strategies of benzoxazoles using 2-aminophenol as a precursor: an up-to-date review

Benzoxazole is a resourceful and important member of the heteroarenes that connects synthetic organic chemistry to medicinal, pharmaceutical, and industrial areas. It is a bicyclic planar molecule and is the most favorable moiety for researchers because it has been extensively used as a starting material for different mechanistic approaches in drug discovery. The motif exhibits a high possibility of broad substrate scope and functionalization to offer several biological activities like anti-microbial, anti-fungal, anti-cancer, anti-oxidant, anti-inflammatory effects, and so on. There has been a large upsurge in the synthesis of benzoxazole via different pathways. The present article presents recent advances in synthetic strategies for benzoxazole derivatives since 2018. A variety of well-organized synthetic methodologies for benzoxazole using 2-aminophenol with aldehydes, ketones, acids, alcohols, isothiocyanates, ortho-esters, and alkynones under different reaction conditions and catalysts, viz. nanocatalysts, metal catalysts, and ionic liquid catalysts, with other miscellaneous techniques has been summarized.

Sustainable Catalytic Synthesis of 2,5-Diformylfuran from Various Carbohydrates

Versatile homogeneous and heterogeneous catalysts that convert carbohydrates to 2,5-diformylfuran (DFF) are essential for the development of sustainable processes for producing high-value chemicals from biomass-derived carbohydrates. An efficient catalytic system consisting of Br−, disulfide, and dimethylsulfoxide (DMSO) promoted the sustainable and selective synthesis of DFF in modest-to-good yields from various carbohydrates, such as fructose, glucose, mannose, galactose, and sucrose. Heterogeneous catalysts containing Br− also facilitated this reaction with recyclable high yields.

Reactions involving aryl methyl ketone and molecular iodine: a powerful tool in the one-pot synthesis of heterocycles

The preparation of heterocyclic compounds has attracted great attention in organic chemistry because of their extensive application in the field of bioactive molecules, materials science, and natural products.

One-step synthesis of 2,5-diformylfuran from monosaccharides by using lanthanum(III) triflate, sulfur, and DMSO

The combination of lanthanum(iii) triflate, sulfur, and dimethyl sulfoxide prompted a facile, direct preparation of 2,5-diformylfuran from glucose and fructose. The one-step dehydration/oxidation of fructose afforded 2,5-diformylfuran in an excellent yield with high selectivity. The proposed mechanism, large-scale synthesis, and product separation were presented. This approach represents a straightforward and eco-friendly pathway, which can be applied in the large-scale production of 2,5-diformylfuran from fructose.